build(ci): add dependabot, auto-merge flows

.github/dependabot.yml

@@ -0,0 +1,21 @@
+# To get started with Dependabot version updates, you'll need to specify which
+# package ecosystems to update and where the package manifests are located.
+# Please see the documentation for all configuration options:
+# https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "daily"
+
+  - package-ecosystem: "npm"
+    directory: "/packages"
+    schedule:
+      interval: "daily"
+
+  - package-ecosystem: "npm"
+    directory: "/packages/voucher"
+    schedule:
+      interval: "daily"

.github/workflows/approve-merge-deps.yml

@@ -0,0 +1,28 @@
+name: Dependabot auto-approve and auto-merge
+on: pull_request
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  dependabot:
+    runs-on: ubuntu-latest
+    if: ${{ github.actor == 'dependabot[bot]' }}
+    steps:
+      - name: Fetch Dependabot metadata
+        id: metadata
+        uses: dependabot/fetch-metadata@HEAD
+        with:
+          github-token: "${{ secrets.GITHUB_TOKEN }}"
+      - name: Approve the PR
+        run: gh pr review --approve "$PR_URL"
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}
+      - name: Merge Dependabot PR
+        if: ${{steps.metadata.outputs.update-type == 'version-update:semver-patch' || steps.metadata.outputs.update-type == 'version-update:semver-minor'}}
+        run: gh pr merge --auto --squash "$PR_URL"
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}