promote GKE database encryption to ga

[nadzir]

As of October 31, GKE database encryption is GA, see https://cloud.google.com/blog/products/containers-kubernetes/exploring-container-security-use-your-own-keys-to-protect-your-data-on-gke

Release Note Template for Downstream PRs (will be copied)

container: Promoted `google_container_cluster` `database_encryption` to GA.

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[nadzir]

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[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 3 files changed, 122 insertions(+), 2 deletions(-))
Terraform Beta: Diff ( 3 files changed, 38 insertions(+), 38 deletions(-))

[modular-magician]

I have triggered VCR tests based on this PR's diffs. See the results here: "https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=122412"

[modular-magician]

Oops! It looks like you're using an unknown release-note type in your changelog entries:

• REPLACEME

Please only use the types listed in https://github.com/GoogleCloudPlatform/magic-modules/blob/master/.ci/RELEASE_NOTES_GUIDE.md.

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 3 files changed, 122 insertions(+), 2 deletions(-))
Terraform Beta: Diff ( 3 files changed, 38 insertions(+), 38 deletions(-))

[modular-magician]

I have triggered VCR tests based on this PR's diffs. See the results here: "https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=122935"