add a PR template

Author: sandan

.github/pull_request_template.md

@@ -0,0 +1,17 @@
+## High level description of this Pull-request
+Include motivations, reasons, and background to add context to your contribution.
+Include a description of changes associated with your commit(s)
+
+## Related Issues
+- List all related issues or NA
+
+## Reviewers
+- Use @Mentions to specify the reviewers for your PR.
+
+# CHECKLIST:
+Make sure all items are marked when you submit the pull-request.
+
+- [ ] Relevant documentation for functions, tests, classes, the wiki, etc. have been made
+- [ ] Necessary unit tests in tests/ pass with no errors
+- [ ] Necessary integration tests in tests/ pass with no errors
+- [ ] Update the CHANGELOG.md with a summary of your changes if requested