Improve danger/changelog/Dangerfile to include the title in the bin/changelog command

Signed-off-by: Rémy Coutable <remy@rymai.me>

danger/changelog/Dangerfile

@@ -2,15 +2,13 @@
 
 require 'yaml'
 
-NO_CHANGELOG_LABELS = %w[backstage QA test].freeze
+NO_CHANGELOG_LABELS = %w[backstage Documentation QA test].freeze
 SEE_DOC = "See [the documentation](https://docs.gitlab.com/ce/development/changelog.html).".freeze
-MISSING_CHANGELOG_MESSAGE = <<~MSG.freeze
-**[CHANGELOG missing](https://docs.gitlab.com/ce/development/changelog.html).**
-
+CREATE_CHANGELOG_MESSAGE = <<~MSG.freeze
 You can create one with:
 
 ```
-bin/changelog -m %<mr_iid>s
+bin/changelog -m %<mr_iid>s "%<mr_title>s"
 ```
 
 If your merge request doesn't warrant a CHANGELOG entry,
@@ -56,13 +54,15 @@ changelog_needed = (gitlab.mr_labels & NO_CHANGELOG_LABELS).empty?
 changelog_found = git.added_files.find { |path| path =~ %r{\A(ee/)?(changelogs/unreleased)(-ee)?/} }
 
 if git.modified_files.include?("CHANGELOG.md")
-  fail "CHANGELOG.md was edited. Please remove the additions and create an entry with `bin/changelog -m #{gitlab.mr_json["iid"]}` instead."
+  fail "**CHANGELOG.md was edited.** Please remove the additions and create a CHANGELOG entry.\n\n" +
+    format(CREATE_CHANGELOG_MESSAGE, mr_iid: gitlab.mr_json["iid"], mr_title: gitlab.mr_json["title"], labels: presented_no_changelog_labels)
 end
 
 if changelog_needed
   if changelog_found
     check_changelog(changelog_found)
   else
-    warn format(MISSING_CHANGELOG_MESSAGE, mr_iid: gitlab.mr_json["iid"], labels: presented_no_changelog_labels)
+    warn "**[CHANGELOG missing](https://docs.gitlab.com/ce/development/changelog.html).**\n\n" +
+      format(CREATE_CHANGELOG_MESSAGE, mr_iid: gitlab.mr_json["iid"], mr_title: gitlab.mr_json["title"], labels: presented_no_changelog_labels)
   end
 end