Set remote build cache to push only if authenticated (#13292)

Author: ribafish

settings.gradle

@@ -19,7 +19,8 @@ gradleEnterprise {
 buildCache {
     local { enabled = System.getenv('CI') != 'true' }
     remote(HttpBuildCache) {
-        push = System.getenv('CI') == 'true'
+        def isAuthenticated = System.getenv('GRADLE_ENTERPRISE_BUILD_CACHE_NODE_USER') && System.getenv('GRADLE_ENTERPRISE_BUILD_CACHE_NODE_KEY')
+        push = System.getenv('CI') == 'true' && isAuthenticated
         enabled = true
         url = 'https://ge.grails.org/cache/'
         credentials {