Following the GitHub docs

I suggest rename .github/ISSUE_TEMPLATE/PULL_REQUEST_TEMPLATE.md to .github/pull_request_template.md 

Right now check-my-repo doesn't seem to support this. 

I was following https://docs.github.com/en/communities/using-templates-to-encourage-useful-issues-and-pull-requests/creating-a-pull-request-template-for-your-repository