fix(deps)!: Update Terraform terraform-google-modules/event-function/google to v4 (#256)

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

Author: renovate[bot]

main.tf

@@ -60,7 +60,7 @@ resource "random_id" "suffix" {
 
 module "main" {
   source  = "terraform-google-modules/event-function/google"
-  version = "~> 3.0"
+  version = "~> 4.0"
 
   entry_point = var.function_entry_point
   event_trigger = {