Add a note to prefer compute_region_instance_template.

[ayberk]

Adds a note to compute_instance_template highlighting the new compute_region_instance_template resource.

Not sure how to test the changes locally -- please let me know if that's required.

Release Note Template for Downstream PRs (will be copied)

[modular-magician]

Hello! I am a robot. It looks like you are a: Community Contributor Googler Core Contributor. Tests will run automatically.

@c2thorn, 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.

You can help make sure that review is quick by doing a self-review and by running impacted tests locally.

[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 ( 2 files changed, 4 insertions(+))
Terraform Beta: Diff ( 2 files changed, 4 insertions(+))