Clarify only user specific change log entries be added (#543)

Author: sliverc

CHANGELOG.md

@@ -28,7 +28,6 @@ any parts of the framework not mentioned in the documentation should generally b
 * Do not render `write_only` relations
 * Do not skip empty one-to-one relationships
 * Allow `HyperlinkRelatedField` to be used with [related urls](https://django-rest-framework-json-api.readthedocs.io/en/stable/usage.html?highlight=related%20links#related-urls)
-* Fixed hardcoded year 2018 in tests ([#539](https://github.com/django-json-api/django-rest-framework-json-api/issues/539))
 * Avoid exception in `AutoPrefetchMixin` when including a reverse one to one relation ([#537](https://github.com/django-json-api/django-rest-framework-json-api/issues/537))
 * Avoid requested resource(s) to be added to included as well ([#524](https://github.com/django-json-api/django-rest-framework-json-api/issues/524))
 

docs/pull_request_template.md

@@ -7,5 +7,5 @@ Fixes #
 - [ ] PR only contains one change (considered splitting up PR)
 - [ ] unit-test added
 - [ ] documentation updated
-- [ ] changelog entry added to `CHANGELOG.md`
+- [ ] `CHANGELOG.md` updated (only for user relevant changes)
 - [ ] author name in `AUTHORS`