Default GKE version is outdates

[bharathkkb]

TL;DR

Default value for GKE version is outdated. We should remove this and default to a release channel.

terraform-google-gke-gitlab/variables.tf

Line 36 in 914a03b

default = "1.21"

Expected behavior

No response

Observed behavior

No response

Terraform Configuration

N/A

Terraform Version

N/A

Additional information

No response