Update pull_request_template.md (#299)

# Summary

Fix PR template formating.

## Proof of Work

<!-- Enter your proof that it works here.-->

## Checklist

- [ ] Have you linked a jira ticket and/or is the ticket in the title?
- [ ] Have you checked whether your jira ticket required DOCSP changes?
- [ ] Have you added changelog file?
    - use `skip-changelog` label if not needed
- refer to [Changelog files and Release
Notes](https://github.com/mongodb/mongodb-kubernetes/blob/master/CONTRIBUTING.md#changelog-files-and-release-notes)
section in CONTRIBUTING.md for more details

Author: MaciejKaras

.github/pull_request_template.md

@@ -12,6 +12,4 @@
 - [ ] Have you checked whether your jira ticket required DOCSP changes?
 - [ ] Have you added changelog file?
     - use `skip-changelog` label if not needed
-    - refer
-      to [Changelog files and Release Notes](https://github.com/mongodb/mongodb-kubernetes/blob/master/CONTRIBUTING.md#changelog-files-and-release-notes)
-      section in CONTRIBUTING.md for more details
+    - refer to [Changelog files and Release Notes](https://github.com/mongodb/mongodb-kubernetes/blob/master/CONTRIBUTING.md#changelog-files-and-release-notes) section in CONTRIBUTING.md for more details