chore: add a workflow to automate the Dependabot PRs

Author: Jarmos-san

.github/workflows/auto-dependabot.yaml

@@ -0,0 +1,42 @@
+# This workflow attempts to automate the Dependabot PRs. Everything here is still WIP and
+# hence is subject to change!
+
+# The following source of documentation has been used to modify the contents of this file:
+# https://docs.github.com/en/code-security/dependabot/working-with-dependabot/automating-dependabot-with-github-actions
+name: Dependabot Auto-Merge
+
+on:
+  pull_request:
+    types:
+      - opened
+      - synchronize
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  dependabot:
+    name: Dependabot
+    runs-on: ubuntu-latest
+    if: github.event.pull_request.user.login == 'dependabot[bot]'
+    steps:
+      - name: Fetch Dependabot Metadata
+        id: metadata
+        uses: dependabot/fetch-metadata@v2.2.0
+        with:
+          github-token: "${{ secrets.GITHUB_TOKEN }}"
+
+      - name: Enable Auto-Merge
+        if: steps.metadata.outputs.update-type == 'version-update:semver-patch'
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GH_TOKEN: ${{secrets.GITHUB_TOKEN}}
+        run: gh pr merge --auto --merge "$PR_URL"
+
+      - name: Auto Approve Pull Request
+        if: github.event.pull_request.user.login == 'dependabot[bot]'
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GH_TOKEN: ${{secrets.GITHUB_TOKEN}}
+        run: gh pr review --approve "$PR_URL"