optional release builder

.github/workflows/xahau-sh-build-in-docker.yml

@@ -3,8 +3,12 @@ name: Release - SH Runner
 on:
   push:
     branches: ["dev", "candidate", "release"]
-  pull_request:
-    branches: ["dev", "candidate", "release"]
+  workflow_dispatch:
+    inputs:
+      reason:
+        description: 'Release Build'
+        required: false
+        default: 'Manual PR testing'
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
@@ -15,6 +19,7 @@ env:
 
 jobs:
   checkout:
+    if: github.event_name == 'push' || github.event_name == 'workflow_dispatch'
     runs-on: [self-hosted, vanity]
     outputs:
       checkout_path: ${{ steps.vars.outputs.checkout_path }}