Create Github Action automation of update-leaderboard.

.github/workflows/leaderboard.yml

@@ -0,0 +1,40 @@
+name: "update-leaderboard"
+on:
+  push:
+    tags-ignore:
+      - 'v*-beta.*'
+  release:
+    types: [published]
+jobs:
+  update-leaderboard:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-go@v2
+        with:
+          go-version: ${{env.GO_VERSION}}
+          stable: true
+      - name: Update Leaderboard
+        id: leaderboard
+        run: |
+          make update-leaderboard
+          echo "::set-output name=changes::$(git status --porcelain)"
+      - name: Create PR
+        if: ${{ steps.leaderboard.outputs.changes != '' }}
+        uses: peter-evans/create-pull-request@v3
+        with:
+          token: ${{ secrets.MINIKUBE_BOT_PAT }}
+          commit-message: Update leaderboard
+          committer: minikube-bot <minikube-bot@google.com>
+          author: minikube-bot <minikube-bot@google.com>
+          branch: leaderboard
+          push-to-fork: minikube-bot/minikube
+          base: master
+          delete-branch: true
+          title: 'Update leaderboard'
+          body: |
+            Committing changes resulting from `make update-leaderboard`.
+            This PR is auto-generated by the [update-leaderboard](https://github.com/kubernetes/minikube/blob/master/.github/workflows/leaderboard.yml) CI workflow.
+            ```
+            ${{ steps.leaderboard.outputs.changes }}
+            ```