`Brightcove` is difficult to migrate because it's subclasses may depend on the signature of the current functions. So it is left as-is for now Note: Tests have not been migrated
Related: #1946, #2908 Authored-by: coletdjnz
Based on https://github.com/ytdl-org/youtube-dl/pull/13449 Closes #1946 Authored by: coletdjnz, kmark