Update provider name in various spots

[rileykarson]

Based on discussion on naming, adopted Terraform provider for Google Cloud / Google Cloud provider

Release Note Template for Downstream PRs (will be copied)

[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 ( 8 files changed, 41 insertions(+), 41 deletions(-)) Terraform Beta: Diff ( 8 files changed, 41 insertions(+), 41 deletions(-))