Normalize music_brainz -> musicbrainz spell

test/music_library_web/live/record_index_test.exs

@@ -296,7 +296,7 @@ defmodule MusicLibraryWeb.RecordIndexTest do
       end)
 
       import_live
-      |> element("#music_brainz_#{first_result_id} button", "CD")
+      |> element("#musicbrainz_#{first_result_id} button", "CD")
       |> render_click()
 
       [record] = MusicLibrary.Repo.all(MusicLibrary.Records.Record)

test/test_helper.exs

@@ -1,5 +1,5 @@
 Mox.defmock(APIBehaviourMock, for: MusicLibrary.Records.MusicBrainz.APIBehaviour)
-Application.put_env(:music_library, :music_brainz, APIBehaviourMock)
+Application.put_env(:music_library, :musicbrainz, APIBehaviourMock)
 
 ExUnit.start()
 Ecto.Adapters.SQL.Sandbox.mode(MusicLibrary.Repo, :manual)