fix prerelease check to allow standard release

[daeho-ro]

I think my previous PR broke the version check logic,

• update prerelease check to allow standard release #19001

Here is the failed actions

• https://github.com/Homebrew/homebrew-core/actions/runs/12514067679/job/34911068323?pr=202542
• https://github.com/Homebrew/homebrew-core/actions/runs/12514611522/job/34911059619?pr=202532

and noticed that the exception should exist. 😥

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[MikeMcQuaid]

Thanks @daeho-ro!