docs: Fix formatting for subnetwork field pattern (#3693)

* docs: Fix formatting for subnetwork field pattern

PiperOrigin-RevId: 492232435

Source-Link: googleapis/googleapis@fcf8211

Source-Link: googleapis/googleapis-gen@ce62e52
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packages/google-cloud-metastore/protos/google/cloud/metastore/v1/metastore.proto

@@ -471,7 +471,7 @@ message NetworkConfig {
       // be at least one IP address available in the subnet's primary range. The
       // subnet is specified in the following form:
       //
-      // `projects/{project_number}/regions/{region_id}/subnetworks/{subnetwork_id}
+      // `projects/{project_number}/regions/{region_id}/subnetworks/{subnetwork_id}`
       string subnetwork = 1 [
         (google.api.field_behavior) = IMMUTABLE,
         (google.api.resource_reference) = {