UI: fix default network is not passed to deployvm API (#7367)

This line was changed in #5080, but reverted in #5151

Author: weizhouapache

ui/src/views/compute/DeployVM.vue

@@ -1634,7 +1634,7 @@ export default {
       this.form.networkids = ids
     },
     updateDefaultNetworks (id) {
-      this.defaultNetwork = id
+      this.defaultnetworkid = id
       this.form.defaultnetworkid = id
     },
     updateNetworkConfig (networks) {