Small change in PR template

.github/pull_request_template.md

@@ -12,7 +12,7 @@ TODO: How can reviewers test the PR?
 # Checklist
 - [ ] Correct base branch was selected (usually `development`)
 - [ ] `development` was merged into this branch and potential conflicts resolved
-- [ ] [Issues](https://github.com/TUMFARSynchrony/experimental-hub/issues) which were solved are referenced
+- [ ] [Issues](https://github.com/TUMFARSynchrony/experimental-hub/issues) which were solved are linked. Be sure to make that manually because Closes/Fixes keywords only work when base branch is main.
 - [ ] Terminology is consistent with the rest of the codebase
 - [ ] Reviewers are assigned
 - [ ] Optional: Wiki pages were updated to reflect the changes (list changed pages above)