review.sh / HTML's review-draft.sh do not work on Linux

[Domenic Denicola]

Apparently the -i '' option to sed is a macOS-ism. See https://stackoverflow.com/a/43453459 and https://unix.stackexchange.com/a/131940 .

I was thinking of trying to fix this but I noticed

    # We should consider merging
    # https://github.com/whatwg/whatwg.org/blob/main/resources.whatwg.org/build/review.sh and
    # https://github.com/whatwg/html/blob/main/review-draft.sh into this script.

which I tend to agree would be a better path. @annevk do you have any interest in giving that a try?

[Domenic Denicola]

I ended up doing this myself, I couldn't resist...