[fix] script style end parsing

[tanhauhau]

continuing #5328 that allows whitespace at the script and style end tag

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Tests

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[dummdidumm]

The regexes allow for arbitrary content after one whitespace, so </script foo> is allowed, but I don't think it is according to the spec, so I would simplify the regex to (in the case of script for example) <\/script\s*>

[pngwn]

Sorry i forgot again didn't i.

This looks good to go.

[Conduitry]

Released in 3.39.0.