Standardise reuse variable from project module and implement for net-vpc (#3205)

* exposing the network_id from the net-vpc module for use with tag bindings

* convert vpc_create to vpc_reuse

* Changed the reuse vars to standardised attributes

* fixed readme tests and schemas

* modified apigee blueprint to use vpc_reuse with network_id passthrough

---------

Co-authored-by: Ludovico Magnocavallo <ludomagno@google.com>

modules/apigee/recipe-apigee-swp/main.tf

@@ -41,8 +41,8 @@ module "project" {
   source = "../../../modules/project"
   name   = var.project_id
   project_reuse = {
-    use_data_source    = var._testing == null
-    project_attributes = var._testing
+    use_data_source = var._testing == null
+    attributes      = var._testing
   }
   services = [
     "apigee.googleapis.com",