Trigger extensions.json generations faster (#550)

* Trigger `extensions.json` generations faster

So that any changes made in this repository take effect right away on the Extensions page in FreshRSS.

* Also when the generate workflow gets updated

.github/workflows/generate.yml

@@ -4,6 +4,14 @@ on:
   schedule:
     - cron: '11 11 * * *'
   workflow_dispatch: ~
+  push:
+    branches: ["main"]
+    paths:
+      - '.github/workflows/generate.yml' # To regenerate extensions.json according to any workflow changes itself
+      - 'xExtension-*/metadata.json' # For version/description updates in official extensions
+      - 'repositories.json' # For new third-party extensions
+      # - 'extensions.json' # Must not be included to avoid causing a commit loop
+      - 'generate.php' # To regenerate extensions.json with the latest approach
 
 permissions:
   contents: write