build: update firebase

Change-Id: I841b4edfaefe307fd6ec3f2b3d76f7e9346f7681

ring-android/app/build.gradle

@@ -111,7 +111,7 @@ dependencies {
 
     implementation 'com.jsibbold:zoomage:1.2.0'
 
-    withFirebaseImplementation 'com.google.firebase:firebase-core:16.0.6'
+    withFirebaseImplementation 'com.google.firebase:firebase-core:16.0.7'
     withFirebaseImplementation 'com.google.firebase:firebase-messaging:17.3.4'
 }