fix: fixing bug with major version generic updater

[faradayfan]

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Fixes #2421 🦕

[google-cla]

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[chingor13]

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[lukasnajman-ext44972]

Hello @faradayfan,
I'm checking in on this pull request. The proposed regex changes would be very helpful for us, as they would allow us to update the version number in our GitHub Action usage samples.
Do you have an estimated timeline for merging these changes?
Thank you for your work on this

[ferrarimarco]

Thanks for this PR. Can you please fix the linting errors? Thanks.

Update: done

[ferrarimarco]

And, can you please add a test for this case in test/updaters/generic.ts?

Thanks!

Update: done