PULL_REQUEST_TEMPLATE

# Description

See [JENKINS-XXXXX](https://issues.jenkins-ci.org/browse/JENKINS-XXXXX).

# Submitter checklist
- [ ] Link to JIRA ticket in description, if appropriate.
- [ ] Change is code complete and matches issue description
- [ ] Appropriate unit or acceptance tests or explanation to why this change has no tests
- [ ] Reviewer's manual test instructions provided in PR description. See Reviewer's first task below.

# Reviewer checklist
- [ ] Run the changes and verified the change matches the issue description
- [ ] Reviewed the code
- [ ] Verified that the appropriate tests have been written or valid explanation given