Add shellcheck workflow

.forgejo/workflows/shellcheck.yml

@@ -0,0 +1,24 @@
+name: Bash Linter
+
+on:
+  push:
+    paths:
+      - '**/*.sh'
+  pull_request:
+    paths:
+      - '**/*.sh'
+
+jobs:
+  lint:
+    runs-on: docker 
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@v3
+
+      - name: Run ShellCheck
+        uses: docker/build-push-action@v2
+
+      - name: Lint Bash Scripts
+        run: |
+          find . -name '*.sh' -print0 | xargs -0 shellcheck
+