Fix net vpc firewall module schema (#3099)

* fix ports in net vpc firewall module schema

* default ports to []

modules/net-vpc-firewall/main.tf

@@ -154,7 +154,7 @@ resource "google_compute_firewall" "custom-rules" {
     iterator = rule
     content {
       protocol = rule.value.protocol
-      ports    = rule.value.ports
+      ports    = try(rule.value.ports, [])
     }
   }
 
@@ -163,7 +163,7 @@ resource "google_compute_firewall" "custom-rules" {
     iterator = rule
     content {
       protocol = rule.value.protocol
-      ports    = rule.value.ports
+      ports    = try(rule.value.ports, [])
     }
   }
 }

modules/net-vpc-firewall/schemas/firewall-rules.schema.json

@@ -88,7 +88,11 @@
               "ports": {
                 "type": "array",
                 "items": {
-                  "type": "number"
+                  "type": [
+                    "integer",
+                    "string"
+                  ],
+                  "pattern": "^[0-9]+(?:-[0-9]+)?$"
                 }
               }
             }