build: use tag for common lib

Signed-off-by: Álvaro Brey <alvaro.brey@nextcloud.com>

app/build.gradle

@@ -353,8 +353,7 @@ dependencies {
     // upon each update first test: new registration, receive push
     gplayImplementation "com.google.firebase:firebase-messaging:23.0.7"
 
-    // TODO change back to tag before merging
-    implementation 'com.github.nextcloud.android-common:ui:783c4b7f6a'
+    implementation 'com.github.nextcloud.android-common:ui:0.2.0'
 }
 
 configurations.all {