Don't advertise the labels that disable changelog requirement

We don't want people to put the wrong labels just to disable the
"changelog needed" message from Danger.

- Labels should be set in accordance to the Throughput guidelines.
- Changelog should be added according to the "What warrants a
  changelog entry?" documentation.
Signed-off-by: Rémy Coutable <remy@rymai.me>

danger/changelog/Dangerfile

@@ -17,7 +17,6 @@ If you want to create a changelog entry for GitLab EE, run the following instead
 bin/changelog --ee -m %<mr_iid>s "%<mr_title>s"
 ```
 
-Note: Merge requests with %<labels>s do not trigger this check.
 MSG
 
 def check_changelog_yaml(path)