Fix Rubocop offense Rails/Presence

We are currently using Object#presence in many places (>65). This commit
fixes the Rubocop TODO offenses running rubocop --auto-correct.

.rubocop_todo.yml

@@ -442,19 +442,6 @@ Rails/LinkToBlank:
     - 'ee/app/helpers/ee/user_callouts_helper.rb'
     - 'ee/app/helpers/license_helper.rb'
 
-# Offense count: 11
-# Cop supports --auto-correct.
-Rails/Presence:
-  Exclude:
-    - 'app/models/ci/pipeline.rb'
-    - 'app/models/concerns/mentionable.rb'
-    - 'app/models/project_services/hipchat_service.rb'
-    - 'app/models/project_services/irker_service.rb'
-    - 'app/models/project_services/jira_service.rb'
-    - 'app/models/project_services/packagist_service.rb'
-    - 'app/models/wiki_page.rb'
-    - 'lib/gitlab/github_import/importer/releases_importer.rb'
-
 # Offense count: 1
 # Cop supports --auto-correct.
 # Configuration parameters: Include.

app/models/ci/pipeline.rb

@@ -584,11 +584,7 @@ module Ci
     def ci_yaml_file_path
       return unless repository_source? || unknown_source?
 
-      if project.ci_config_path.blank?
-        '.gitlab-ci.yml'
-      else
-        project.ci_config_path
-      end
+      project.ci_config_path.presence || '.gitlab-ci.yml'
     end
 
     def ci_yaml_file

app/models/concerns/mentionable.rb

@@ -150,7 +150,7 @@ module Mentionable
   #
   # Returns a Hash.
   def detect_mentionable_changes
-    source = (changes.present? ? changes : previous_changes).dup
+    source = (changes.presence || previous_changes).dup
 
     mentionable = self.class.mentionable_attrs.map { |attr, options| attr }
 

app/models/project_services/hipchat_service.rb

@@ -73,7 +73,7 @@ class HipchatService < Service
   private
 
   def gate
-    options = { api_version: api_version.present? ? api_version : 'v2' }
+    options = { api_version: api_version.presence || 'v2' }
     options[:server_url] = server unless server.blank?
     @gate ||= HipChat::Client.new(token, options)
   end

app/models/project_services/irker_service.rb

@@ -36,8 +36,8 @@ class IrkerService < Service
 
   def settings
     {
-      server_host: server_host.present? ? server_host : 'localhost',
-      server_port: server_port.present? ? server_port : 6659
+      server_host: server_host.presence || 'localhost',
+      server_port: server_port.presence || 6659
     }
   end
 

app/models/project_services/jira_service.rb

@@ -339,7 +339,7 @@ class JiraService < IssueTrackerService
   end
 
   def client_url
-    api_url.present? ? api_url : url
+    api_url.presence || url
   end
 
   def reset_password?

app/models/project_services/packagist_service.rb

@@ -59,7 +59,7 @@ class PackagistService < Service
   end
 
   def hook_url
-    base_url = server.present? ? server : 'https://packagist.org'
+    base_url = server.presence || 'https://packagist.org'
     "#{base_url}/api/update-package?username=#{username}&apiToken=#{token}"
   end
 end

app/models/wiki_page.rb

@@ -77,11 +77,7 @@ class WikiPage
 
   # The escaped URL path of this page.
   def slug
-    if @attributes[:slug].present?
-      @attributes[:slug]
-    else
-      wiki.wiki.preview_slug(title, format)
-    end
+    @attributes[:slug].presence || wiki.wiki.preview_slug(title, format)
   end
 
   alias_method :to_param, :slug

lib/gitlab/github_import/importer/releases_importer.rb

@@ -47,11 +47,7 @@ module Gitlab
         end
 
         def description_for(release)
-          if release.body.present?
-            release.body
-          else
-            "Release for tag #{release.tag_name}"
-          end
+          release.body.presence || "Release for tag #{release.tag_name}"
         end
       end
     end