docs: shift pr template up a dir

.github/pull_request_template.md

@@ -0,0 +1,16 @@
+### PR Checklist
+
+- [ ] Brief description of changes
+- [ ] Links to any relevant issues
+- [ ] Required status checks are passing
+- [ ] User cases if changes impact the user's experience
+- [ ] `@mention` a maintainer to request a review
+
+<!--
+  Links
+  -->
+
+<!-- prettier-ignore-start -->
+[blog]: https://circleci.com/blog/triggering-trusted-ci-jobs-on-untrusted-forks/
+[script]: https://github.com/jklukas/git-push-fork-to-upstream-branch
+<!-- prettier-ignore-end -->