Terraform: update AKS version (#1556)
Terraform: update AKS version (#1556)

Update AKS to 1.15.10.
googleforgames/agones,googleforgames/agones,googleforgames/agones,googleforgames/agones,googleforgames/agones,googleforgames/agones,googleforgames/agones,googleforgames/agones