Setup nighlty build + GitHub action

app/src/nightly/google-services.json

@@ -0,0 +1,40 @@
+{
+  "project_info": {
+    "project_number": "912726360885",
+    "firebase_url": "https://vector-alpha.firebaseio.com",
+    "project_id": "vector-alpha",
+    "storage_bucket": "vector-alpha.appspot.com"
+  },
+  "client": [
+    {
+      "client_info": {
+        "mobilesdk_app_id": "1:912726360885:android:e17435e0beb0303000427c",
+        "android_client_info": {
+          "package_name": "io.element.android.x.nightly"
+        }
+      },
+      "oauth_client": [
+        {
+          "client_id": "912726360885-e87n3jva9uoj4vbidvijq78ebg02asv2.apps.googleusercontent.com",
+          "client_type": 3
+        }
+      ],
+      "api_key": [
+        {
+          "current_key": "AIzaSyAFZX8IhIfgzdOZvxDP_ISO5WYoU7jmQ5c"
+        }
+      ],
+      "services": {
+        "appinvite_service": {
+          "other_platform_oauth_client": [
+            {
+              "client_id": "912726360885-e87n3jva9uoj4vbidvijq78ebg02asv2.apps.googleusercontent.com",
+              "client_type": 3
+            }
+          ]
+        }
+      }
+    }
+  ],
+  "configuration_version": "1"
+}