Actions: Adding JSON validation

.github/workflows/validate_json.yml

@@ -0,0 +1,18 @@
+name: Sellers.json validation
+on:
+  push:
+    branches:
+    - main
+  pull_request:
+    branches:
+    - main
+
+jobs:
+  verify-json-validation:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          path: './'
+      - run: |
+          cat sellers.json | jq -e