Add custom actionlint workflow to bypass the one in brew style

https://github.com/Homebrew/brew/blob/123bf791ec1c167f7a3bbec50a438ba50f97d478/Library/Homebrew/style.rb#L94-L99

Author: tangrufus

.github/actionlint.yml

@@ -0,0 +1,2 @@
+config-variables:
+  - TASTENDRUCK_APP_ID

.github/workflows/actionlint.yml

@@ -0,0 +1,26 @@
+name: Actionlint
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref_name }}-${{ github.event.pull_request.number || github.sha }}
+  cancel-in-progress: true
+
+permissions: {}
+
+jobs:
+  actionlint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          sparse-checkout: .github
+
+      - name: Check workflow files
+        uses: docker://rhysd/actionlint:latest
+        with:
+          args: -color