Fix capitalization of "merge requests"

We shouldn't be capitalizing the "R" in "merge requests" ever, and
we should only capitalize the "M" when it's the first word in a
sentence or slug.

Any other capitalization looks strange to native English speakers.

app/views/notify/_successful_pipeline.text.erb

@@ -3,7 +3,7 @@
 Project: <%= @project.name %> ( <%= project_url(@project) %> )
 Branch: <%= @pipeline.source_ref %> ( <%= commits_url(@pipeline) %> )
 <% if @merge_request -%>
-Merge Request: <%= @merge_request.to_reference %> ( <%= merge_request_url(@merge_request) %> )
+Merge request: <%= @merge_request.to_reference %> ( <%= merge_request_url(@merge_request) %> )
 <% end -%>
 
 Commit: <%= @pipeline.short_sha %> ( <%= commit_url(@pipeline) %> )

app/views/notify/closed_merge_request_email.html.haml

 %p
-  Merge Request #{merge_request_reference_link(@merge_request)}
+  Merge request #{merge_request_reference_link(@merge_request)}
   was closed by #{sanitize_name(@updated_by.name)}

app/views/notify/closed_merge_request_email.text.haml

-Merge Request #{@merge_request.to_reference} was closed by #{sanitize_name(@updated_by.name)}
+Merge request #{@merge_request.to_reference} was closed by #{sanitize_name(@updated_by.name)}
 
-Merge Request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
+Merge request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
 
 = merge_path_description(@merge_request, 'to')
 

app/views/notify/merge_request_status_email.html.haml

 %p
-  Merge Request #{merge_request_reference_link(@merge_request)}
+  Merge request #{merge_request_reference_link(@merge_request)}
   was #{@mr_status} by #{sanitize_name(@updated_by.name)}

app/views/notify/merge_request_status_email.text.haml

-Merge Request #{@merge_request.to_reference} was #{@mr_status} by #{sanitize_name(@updated_by.name)}
+Merge request #{@merge_request.to_reference} was #{@mr_status} by #{sanitize_name(@updated_by.name)}
 
-Merge Request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
+Merge request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
 
 = merge_path_description(@merge_request, 'to')
 

app/views/notify/merge_request_unmergeable_email.html.haml

 %p
-  Merge Request #{merge_request_reference_link(@merge_request)} can no longer be merged due to conflict.
+  Merge request #{merge_request_reference_link(@merge_request)} can no longer be merged due to conflict.

app/views/notify/merge_request_unmergeable_email.text.haml

-Merge Request #{@merge_request.to_reference} can no longer be merged due to conflict.
+Merge request #{@merge_request.to_reference} can no longer be merged due to conflict.
 
-Merge Request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
+Merge request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
 
 = merge_path_description(@merge_request, 'to')
 

app/views/notify/merge_when_pipeline_succeeds_email.text.haml

-Merge Request #{@merge_request.to_reference} was scheduled to merge after pipeline succeeds by #{sanitize_name(@mwps_set_by.name)}
+Merge request #{@merge_request.to_reference} was scheduled to merge after pipeline succeeds by #{sanitize_name(@mwps_set_by.name)}
 
-Merge Request url: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
+Merge request url: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
 
 = merge_path_description(@merge_request, 'to')
 

app/views/notify/merged_merge_request_email.html.haml

 %p
-  Merge Request #{merge_request_reference_link(@merge_request)} was merged
+  Merge request #{merge_request_reference_link(@merge_request)} was merged

app/views/notify/merged_merge_request_email.text.haml

-Merge Request #{@merge_request.to_reference} was merged
+Merge request #{@merge_request.to_reference} was merged
 
-Merge Request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
+Merge request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
 
 = merge_path_description(@merge_request, 'to')
 

app/views/notify/new_mention_in_merge_request_email.html.haml

 %p
-  You have been mentioned in Merge Request #{merge_request_reference_link(@merge_request)}
+  You have been mentioned in merge request #{merge_request_reference_link(@merge_request)}
 
 = render template: 'notify/new_merge_request_email'

app/views/notify/new_mention_in_merge_request_email.text.erb

-You have been mentioned in Merge Request <%= @merge_request.to_reference %>
+You have been mentioned in merge request <%= @merge_request.to_reference %>
 
 <%= url_for(project_merge_request_url(@merge_request.target_project, @merge_request)) %>
 

app/views/notify/pipeline_failed_email.text.erb

@@ -3,7 +3,7 @@ Pipeline #<%= @pipeline.id %> has failed!
 Project: <%= @project.name %> ( <%= project_url(@project) %> )
 Branch: <%= @pipeline.source_ref %> ( <%= commits_url(@pipeline) %> )
 <% if @merge_request -%>
-Merge Request: <%= @merge_request.to_reference %> ( <%= merge_request_url(@merge_request) %> )
+Merge request: <%= @merge_request.to_reference %> ( <%= merge_request_url(@merge_request) %> )
 <% end -%>
 
 Commit: <%= @pipeline.short_sha %> ( <%= commit_url(@pipeline) %> )

app/views/notify/push_to_merge_request_email.text.haml

 #{sanitize_name(@updated_by_user.name)} pushed new commits to merge request #{@merge_request.to_reference}
 
-Merge Request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
+Merge request URL: #{project_merge_request_url(@merge_request.target_project, @merge_request)}
 \
 - if @existing_commits.any?
   - count = @existing_commits.size

app/views/notify/reassigned_merge_request_email.text.erb

-Reassigned Merge Request <%= @merge_request.iid %>
+Reassigned merge request <%= @merge_request.iid %>
 
 <%= url_for([@merge_request.project, @merge_request, { only_path: false }]) %>
 

app/views/notify/resolved_all_discussions_email.html.haml

 %p
-  All discussions on Merge Request #{merge_request_reference_link(@merge_request)}
+  All discussions on merge request #{merge_request_reference_link(@merge_request)}
   were resolved by #{sanitize_name(@resolved_by.name)}

app/views/notify/resolved_all_discussions_email.text.erb

-All discussions on Merge Request <%= @merge_request.to_reference %> were resolved by <%= sanitize_name(@resolved_by.name) %>
+All discussions on merge request <%= @merge_request.to_reference %> were resolved by <%= sanitize_name(@resolved_by.name) %>
 
 <%= url_for(project_merge_request_url(@merge_request.target_project, @merge_request)) %>

spec/mailers/emails/merge_requests_spec.rb

@@ -31,7 +31,7 @@ RSpec.describe Emails::MergeRequests do
       aggregate_failures do
         is_expected.to have_referable_subject(merge_request, reply: true)
         is_expected.to have_body_text(project_merge_request_path(project, merge_request))
-        is_expected.to have_body_text('You have been mentioned in Merge Request')
+        is_expected.to have_body_text('You have been mentioned in merge request')
         is_expected.to have_link(merge_request.to_reference, href: project_merge_request_url(merge_request.target_project, merge_request))
         is_expected.to have_text_part_content(assignee.name)
         is_expected.to have_text_part_content(reviewer.name)