chore: add commit message categories to PR template (Azure#421)

.github/PULL_REQUEST_TEMPLATE.md

@@ -15,7 +15,20 @@ And read this for faster PR reviews: https://github.com/kubernetes/community/blo
 
 **Requirements**:
 <!-- Put an "X" character inside the brackets of each completed task. Some may be optional depending on the PR. -->
+
 - [ ] uses [conventional commit messages](https://www.conventionalcommits.org/)
+  <!-- Common commit types:
+        build: Build 🏭
+        chore: Maintenance 🔧
+        ci: Continuous Integration 💜
+        docs: Documentation 📘
+        feat: Features 🌈
+        fix: Bug Fixes 🐞
+        perf: Performance Improvements 🚀
+        refactor: Code Refactoring 💎
+        revert: Revert Change ◀️
+        style: Code Style 🎶
+        test: Testing 💚 -->
 - [ ] includes documentation
 - [ ] adds unit tests
 - [ ] tested upgrade from previous version