Update What Warrants a Changelog Entry for Documentation Changes

doc/development/changelog.md

@@ -101,6 +101,7 @@ EE: true
 - _Any_ contribution from a community member, no matter how small, **may** have
   a changelog entry regardless of these guidelines if the contributor wants one.
 - Any [GLEX experiment](experiment_guide/gitlab_experiment.md) changes **should not** have a changelog entry.
+- An MR that includes only documentation changes **should not** have a changelog entry.
 
 For more information, see
 [how to handle changelog entries with feature flags](feature_flags/index.md#changelog).