chore(ci): add lumapps github actions validator workflow

Author: aureldent

.github/workflows/github-actions-validator.yml

@@ -0,0 +1,17 @@
+---
+  name: 'CI: github-actions-validator'
+  
+  on:
+      pull_request:
+  
+  concurrency:
+      group: ${{ github.head_ref }}-github-actions-validator
+      cancel-in-progress: true
+  
+  jobs:
+      github-actions-validator:
+          name: Github-actions-validator
+          runs-on: ubuntu-latest
+          steps:
+              - uses: actions/checkout@v3
+              - uses: lumapps/github-actions-validator@v1