Adopt PR icons in CAPO (#496)

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,10 +1,5 @@
-<!--  Thanks for sending a pull request!  Here are some tips for you:
-1. If this is your first time, read our contributor guidelines https://git.k8s.io/community/contributors/guide/pull-requests.md#the-pull-request-submit-process and developer guide https://git.k8s.io/community/contributors/devel/development.md#development-guide
-2. If you want *faster* PR reviews, read how: https://git.k8s.io/community/contributors/guide/pull-requests.md#best-practices-for-faster-reviews
-3. Follow the instructions for writing a release note: https://git.k8s.io/community/contributors/guide/release-notes.md
-4. If the PR is unfinished, see how to mark it: https://git.k8s.io/community/contributors/guide/pull-requests.md#marking-unfinished-pull-requests
-5. If this PR changes image versions, please title this PR "Bump <image name> from x.x.x to y.y.y."
--->
+<!-- please add a icon to the title of this PR (see https://sigs.k8s.io/cluster-api/VERSIONING.md), and delete this line and similar ones -->
+<!-- the icon will be either ⚠️ (:warning:, major or breaking changes), ✨ (:sparkles:, minor or feature additions), 🐛 (:bug:, patch and bugfixes), 📖 (:book:, documentation or proposals), or 🏃 (:running:, other) -->
 
 **What this PR does / why we need it**:
 

CONTRIBUTING.md

@@ -21,3 +21,4 @@ Kubernetes projects require that you sign a Contributor License Agreement (CLA)
 1. If your proposed change is accepted, and you haven't already done so, sign a Contributor License Agreement (see details above).
 1. Fork the desired repo, develop and test your code changes.
 1. Submit a pull request.
+1. All code PR must be labeled with ⚠️ (⚠️, major or breaking changes), ✨ (✨, minor or feature additions), 🐛 (🐛, patch and bugfixes), 📖 (📖, documentation or proposals), or 🏃 (🏃, other).