chore(ci): enable dependabot auto-merging (#110)

Author: danieleades

.github/workflows/CI.yml

@@ -48,13 +48,21 @@ jobs:
   msrv:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@master
-      - name: Get MSRV from Cargo.toml
-        run: |
-          MSRV=$(grep 'rust-version' Cargo.toml | sed 's/.*= *"\(.*\)".*/\1/')
-          echo "MSRV=$MSRV" >> $GITHUB_ENV
-      - uses: dtolnay/rust-toolchain@master
-        with:
-          toolchain: ${{ env.MSRV }}
-      - uses: taiki-e/install-action@cargo-no-dev-deps
-      - run: cargo no-dev-deps check --all
+      - uses: actions/checkout@v6
+      - uses: taiki-e/install-action@cargo-hack
+      - run: cargo hack --no-dev-deps --rust-version check --all
+
+  # Automatically merge if it's a Dependabot PR that passes the build
+  dependabot:
+    needs: [test, fmt, clippy, cargo-deny, msrv]
+    permissions:
+      contents: write
+      pull-requests: write
+    runs-on: ubuntu-latest
+    if: github.actor == 'dependabot[bot]'
+    steps:
+      - name: Enable auto-merge for Dependabot PRs
+        run: gh pr merge --auto --squash "$PR_URL"
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GH_TOKEN: ${{secrets.GITHUB_TOKEN}}