Add cAdvisor Metrics to Autopilot/Standard GKE Cluster

[HeiglAnna]

Added cAdvisor to the Monitoring Block to be able to collect and view cAdvisor metrics in Cloud Monitoring.

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Checklist

I applicable, I acknowledge that I have:

• [x ] Read the contributing guide
• [ x] Ran terraform fmt on all modified files
• [ x] Regenerated the relevant README.md files using tools/tfdoc.py
• [ x] Made sure all relevant tests pass

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[juliocc]

Hi @HeiglAnna, could you please take a look at the failing tests so we can merge this?

Thanks!

[HeiglAnna]

@juliocc I'm not quite sure on the linting errors in the documentation

Checking locally, there are no errors in the lint.sh nor check_documentation

[juliocc]

@juliocc I'm not quite sure on the linting errors in the documentation

Checking locally, there are no errors in the lint.sh nor check_documentation

I've sent you a PR with the fixes. Merge it to your branch and then everything should pass here.

[juliocc]

All good now. Thanks for your contribution @AnnaHeigl!