ci: add workflow dispatch trigger

Author: NoelJacob

.github/workflows/apbx.yaml

@@ -6,6 +6,13 @@ on:
       - "src/**"
       - "**/*.yaml"
       - "**/*.yml"
+  workflow_dispatch:
+    inputs:
+      branch:
+        description: 'Branch or ref to run workflow on'
+        required: true
+        default: 'main'
+        type: string
 
 env:
   SXSC_REPO: "https://github.com/Atlas-OS/sxsc"
@@ -18,7 +25,7 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.ref }}
+          ref: ${{ github.event_name == 'workflow_dispatch' && github.event.inputs.branch || github.ref }}
           token: ${{ secrets.RUNNER_SECRET }}
 
       - name: Validate YAML files