Use setup-gcloud@v0.3.0 instead of @master

[imjasonh]

Shouldn't be referring to workflow actions from a moving source, for security and stability.

see google-github-actions/setup-gcloud#451

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• Includes unit tests
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Reviewer Notes

• The code flow looks good.
• Unit tests and or integration tests added.

[sethvargo]

@imjasonh we reverted the branch rename for now, but this is a good change. I'd recommend pinning to @v0 if you want to avoid needing to upgrade to specific versions. Pinning to a specific version is best for security though.

[imjasonh]

@imjasonh we reverted the branch rename for now, but this is a good change. I'd recommend pinning to @v0 if you want to avoid needing to upgrade to specific versions. Pinning to a specific version is best for security though.

Yep, this never should have been @master. 👍