Update the pull-request-template. (#54)

* Update the pull-request-template.

pull_request_template.md

@@ -0,0 +1,29 @@
+### Purpose
+_Please explain the purpose of this PR and include links to any GitHub issues that it fixes:_
+
+- No issue is linked to this PR.
+---
+### Changes
+_Please list out what major changes were made in this PR to address the issue:_
+
+- No changes.
+---
+### Review Instructions
+_Please provide instructions about how should a reviewer test/verify the changes in this PR:_
+
+- No instructions.
+
+---
+### PR Checklist
+_Please ensure the following when opening a PR:_
+
+- [ ] This PR added or updated tests.
+- [ ] This PR updated docstrings or documentation.
+- [ ] This PR applied Python style guidelines, specifically followed [NumPy style docstrings](https://sphinxcontrib-napoleon.readthedocs.io/en/latest/example_numpy.html) for this repo.
+- [ ] This PR considered generalizability beyond our own use case.
+
+---
+### Follow-up Discussions
+_Please append follow-up discussions and issues during the review process below:_
+
+- No follow-up discussions.