Create PULL_REQUEST_TEMPLATE.md

.github/PULL_REQUEST_TEMPLATE.md

+**What type of PR is this?**
+> Uncomment only one ` /kind <>` line, hit enter to put that in a new line, and remove leading whitespaces from that line:
+>
+> /kind api-change
+> /kind bug
+> /kind cleanup
+> /kind design
+> /kind documentation
+> /kind failing-test
+> /kind feature
+> /kind flake
+
+**What this PR does / why we need it**:
+
+**Which issue(s) this PR fixes**:
+<!--
+Usage: `Fixes #<issue number>`, or `Fixes (paste link of issue)`.
+_If PR is about `failing-tests or flakes`, please post the related issues/tests in a comment and do not use `Fixes`_*
+-->
+Fixes #
+
+**Special notes for reviewers**:
+```
+```
+
+**Additional documentation, usage docs, etc.**:
+
+<!--
+This section can be blank if this pull request does not require a release note.
+Please use the following format for linking documentation or pass the
+section below:
+- [KEP]: <link>
+- [Usage]: <link>
+- [Other doc]: <link>
+-->
+```docs
+
+```