docs: updated changelog entry to PR template

Author: mtrezza

.github/pull_request_template.md

@@ -22,9 +22,8 @@ Related issue: FILL_THIS_OUT
     Delete suggested TODOs that do not apply to this PR.
 -->
 
-- [ ] Add test cases
-- [ ] Add entry to changelog
+- [ ] Add tests
 - [ ] Add changes to documentation (guides, repository pages, in-code descriptions)
 - [ ] Add [security check](https://github.com/parse-community/parse-server/blob/master/CONTRIBUTING.md#security-checks)
 - [ ] Add new Parse Error codes to Parse JS SDK <!-- no hard-coded error codes in Parse Server -->
-- [ ] ...
+- [x] A changelog entry is created automatically using the pull request title (do not manually add a changelog entry)