Add the ShellCheck workflow

.github/workflows/shellcheck.yaml

@@ -0,0 +1,20 @@
+name: shellcheck
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  shellcheck:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install ShellCheck
+        run: |
+          sudo apt-get -y update
+          sudo apt-get -y install shellcheck
+      - name: Analyze the scripts with ShellCheck
+        run: |
+          shellcheck action_launcher.bash