Bring text mail for new issue & MR more in line

Make these templates for mail notifications for a new issue and a new
merge request more similar.

Also remove some leading whitespace in text mails.

app/views/notify/new_issue_email.text.erb

-<%= sanitize_name(@issue.author_name) %> <%= 'created an issue:' %>
+<%= sanitize_name(@issue.author_name) %> <%= 'created an issue:' %> <%= url_for(project_issue_url(@issue.project, @issue)) %>
 
-<% if @issue.assignees.any? -%>
-  <%= assignees_label(@issue) %>
-<% end %>
+<%= assignees_label(@issue) if @issue.assignees.any? %>
 
-<% if @issue.description -%>
-  <%= @issue.description %>
-<% end %>
+<%= @issue.description %>

app/views/notify/new_merge_request_email.text.erb

-<%= @merge_request.author_name %> <%= 'created a merge request:' %> <%= url_for(project_merge_request_url(@merge_request.target_project, @merge_request)) %>
+<%= sanitize_name(@merge_request.author_name) %> <%= 'created a merge request:' %> <%= url_for(project_merge_request_url(@merge_request.target_project, @merge_request)) %>
 
 <%= merge_path_description(@merge_request, 'to') %>
 <%= 'Author:' %>    <%= @merge_request.author_name %>
-<%= assignees_label(@merge_request) %>
+<%= assignees_label(@merge_request) if @merge_request.assignees.any? %>
 <%= render_if_exists 'notify/merge_request_approvers', presenter: @mr_presenter %>
 
 <%= @merge_request.description %>

changelogs/unreleased/tc-cleanup-issue-created-text-mail.yml

+---
+title: Bring text mail for new issue & MR more in line
+merge_request: 32254
+author:
+type: changed