Only auth and push on master branch

[damccorm]

This will fix issues like #29992 (comment)

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[damccorm]

R: @Abacn

I can't really test this change well since the workflow_dispatch trigger wasn't configured, so I'd vote we merge and iterate on it if needed

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control

[Abacn]

Thanks for the fix!