fix(deps)!: Update Terraform terraform-google-modules/network/google to v8 (#73)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

modules/private_network/main.tf

@@ -16,7 +16,7 @@
 
 module "vpc" {
   source       = "terraform-google-modules/network/google"
-  version      = "~> 6.0"
+  version      = "~> 8.0"
   project_id   = var.project_id
   network_name = var.network_name
   routing_mode = "GLOBAL"