add metadata_gce grain to handle googles new style of metadata server, which is not ec2 compat

[whytewolf]

What does this PR do?

Adds a new grain module to handle metadata for gce. since google has created their own standard for metadata servers, that is not ec2 compatible.

What issues does this PR fix or reference?

Fixes: #52332

Previous Behavior

No grains created for meta data information

New Behavior

New grains created that follow the layout of googles metadata

Merge requirements satisfied?

[NOTICE] Bug fixes or features added to Salt require tests.

• Docs
• Changelog - https://docs.saltproject.io/en/master/topics/development/changelog.html
• Tests written/updated

Commits signed with GPG?

No

[github-actions]

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