FIX: Add additional HTML5 media extensions to onebox audio and video tags (PR #8216)

Modern browsers support more file extensions than the ones we’re currently specifying (source).

For example, Ogg files usually have the .ogg extension, but can also have .ogv (for video) and .oga (for audio).

Including these additional extensions ensures that valid media files will appear with an HTML audio/video player.

GitHub

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This seems good to me, thank you!