[6.4.x] Sema: Improve UseAnyAppleOSAvailability diagnostics#88974

tshortli wants to merge 4 commits intoswiftlang:release/6.4.xswiftlang/swift:release/6.4.xfrom

tshortli:improve-use-any-apple-os-diags-6.4.xtshortli/swift:improve-use-any-apple-os-diags-6.4.xCopy head branch name to clipboard