use ubuntu-22.04 to fix rpm instakll (unshare) issues

Author: oliverkurth

.github/workflows/photon-os-installer.yml

@@ -4,7 +4,7 @@ on: [pull_request, push, workflow_dispatch]
 
 jobs:
   build:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
 
     steps:
     - name: Checkout code