Run android-validate-gradle-wrapper on every matching push

This prevents the following possible ways of commiting a malicious
gradle-wrapper.jar to the repository:
* Commiting to another path than the one previously specified
* Pushing to `main` without going through a PR

.github/workflows/android-validate-gradle-wrapper.yml

@@ -2,10 +2,10 @@ name: "Android - Validate gradle wrapper"
 
 on:
   workflow_dispatch:
-  pull_request:
+  push:
     paths:
       - .github/workflows/android-validate-gradle-wrapper.yml
-      - android/gradle/wrapper/gradle-wrapper.jar
+      - '**/gradle-wrapper.jar'
 
 permissions: {}