feat: create default VPC network if it does not exist already (#1052)

* feat: create `default` network if it does not exist already

* fix: comments must end with a period

Author: lvaylet

provisioning/terraform/network.tf

@@ -0,0 +1,26 @@
+# Copyright 2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Define a data source to fetch the `default` VPC network.
+data "google_compute_network" "default" {
+  name = "default"
+}
+
+# Create the `default` VPC network if it does not exist.
+resource "google_compute_network" "default" {
+  name = "default"
+
+  # Only create the network if it does not exist.
+  count = data.google_compute_network.default.name == "" ? 1 : 0
+}