add depup

.github/workflows/depup.yml

@@ -0,0 +1,31 @@
+name: depup
+on:
+  schedule:
+    - cron: '35 9 * * *'
+
+jobs:
+  depup:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+
+      - uses: haya14busa/action-depup@v1
+        id: depup
+        with:
+          file: Dockerfile
+          version_name: REVIEWDOG_VERSION
+          repo: reviewdog/reviewdog
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v2
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          title: "chore(deps): update reviewdog to ${{ steps.depup.outputs.latest }}"
+          commit-message: "chore(deps): update reviewdog to ${{ steps.depup.outputs.latest }}"
+          body: |
+            Update reviewdog to [${{ steps.depup.outputs.latest }}](https://github.com/reviewdog/reviewdog/releases/tag/v${{ steps.depup.outputs.latest }})
+
+            This PR is auto generated by [depup workflow](https://github.com/${{ github.repository }}/actions?query=workflow%3Adepup).
+          branch: depup/reviewdog
+          base: master
+          labels: 'bump:patch'