PHP 8.5: Replace non-canonical scalar type casts with canonical versions

[TobiasBg]

PHP 8.5 deprecates non-canonical scalar type casts (boolean|double|integer|binary). Therefore, their canonical versions should be used.

See https://php.watch/versions/8.5/boolean-double-integer-binary-casts-deprecated.

The changes in this commit are the only non-canonical scalar type cases in Core files that are maintained directly.
Another occurrence has been submitted for getID3 upstream.

This PR is handled as part of https://core.trac.wordpress.org/ticket/63061.

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[github-actions]

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[swissspidy]

Thank you!

[SergeyBiryukov]

Thanks for the PR! Merged in r60659.