Skip tests due to GKE version constraints

[slevenick]

These tests try to update the GKE version to the previous available version, but in this case due to the available versions on the API that is results in attempting to downgrade the minor version which is not allowed.

Ignore these tests until another available version comes out that is on the same minor version as the latest

Fixes: hashicorp/terraform-provider-google#6405

Release Note Template for Downstream PRs (will be copied)

[modular-magician]

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

Diff report:

Terraform GA: Diff ( 1 file changed, 4 insertions(+))
Terraform Beta: Diff ( 1 file changed, 4 insertions(+))