fix(kubernetes): Use stable version of gcp k8s module

Context

A new version of the private_cluster module provided by google is breaking shared services deployment.

In vc-modules-gcp!93 (merged) I use ~> as (suggested by Hashicorp) to set the version of the module to 40.X.X, and avoid automatically upgrading the modules version.

Impact

Fixes incompatible version constraints issues while initializing shared services.

Test(s)

Deploy vc-shared-services using this patch.

Links

GCP modules MR: vc-modules-gcp!93 (merged)