replace auto_restart with automatic_restart

[femnad]

The argument used by the google_compute_instance resource is called automatic_restart, update documentation to reflect that.

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[modular-magician]

Hello! I am a robot. It looks like you are a community contributor. @slevenick, a repository maintainer, has been assigned to review your changes. If you have not received review feedback within 2 business days, please leave a comment on this PR asking them to take a look.

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[slevenick]

Thanks! I'll wait for the build to complete before merging

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

Terraform GA: Diff ( 3 files changed, 3 insertions(+), 3 deletions(-))
Terraform Beta: Diff ( 3 files changed, 3 insertions(+), 3 deletions(-))
TF Conversion: Diff ( 2 files changed, 3 insertions(+), 3 deletions(-))