Fix lint error

Author: rmosolgo

spec/dummy/test/controllers/dashboard/subscriptions/topics_controller_test.rb

@@ -21,7 +21,7 @@ def test_it_renders_empty_state_and_not_found_states
 
   def test_it_lists_topics_and_shows_detail
     DummySchema.subscriptions.clear
-    res1 = DummySchema.execute("subscription { message(channel: \"cats\") }")
+    _res1 = DummySchema.execute("subscription { message(channel: \"cats\") }")
     res2 = DummySchema.execute("subscription { message(channel: \"dogs\") }")
     DummySchema.subscriptions.trigger(:message, { channel: "dogs"}, "Woof!")
     get graphql_dashboard.subscriptions_topics_path