message: test: fix typo
  Cr-Commit-Position: refs/heads/master@{#31357}
diff: @@ -4599,7 +4599,7 @@ TEST_F(MediaSessionDescriptionFactoryTest, TestSetAudioCodecs) {
  // properly.
  send_codecs[1].channels = 0;
  - // Alther iLBC receive codec to be lowercase, to test that case conversions
  + // Alter iLBC receive codec to be lowercase, to test that case conversions
  // are handled properly.
  recv_codecs[2].name = "ilbc";
  