Submariner Add-on install fails on GCP Cluster with "Shared VPC"

Issue

• Is it possible to Submariner addon on cluster with Shared VPC?

• We have ACM installed and are moving into using Submariner add-on for the cross-cluster communications that it provides. The submariner operator and other resources were deployed fine, but in the events of an error for the initial Firewall creation:

  Error creating firewall rule "ocp-test-submariner-public-ports-ingress": error inserting firewall rule &compute.Firewall{Allowed:[]*compute.FirewallAllowed{(*compute.FirewallAllowed)(0xc0019d6960), (*compute.FirewallAllowed)(0xc0019d69c0), (*compute.FirewallAllowed)(0xc0019d6a80), (*compute.FirewallAllowed)(0xc0019d6ae0)}, CreationTimestamp:"", Denied:[]*compute.FirewallDenied(nil), Description:"", DestinationRanges:[]string(nil), Direction:"INGRESS", Disabled:false, Id:0x0, Kind:"", LogConfig:(*compute.FirewallLogConfig)(nil), Name:"ocp-test-submariner-public-ports-ingress", Network:"projects/ocptest/global/networks/ocp-test-network", Priority:0, SelfLink:"", SourceRanges:[]string(nil), SourceServiceAccounts:[]string(nil), SourceTags:[]string(nil), TargetServiceAccounts:[]string(nil), TargetTags:[]string{"submariner-io-gateway-node"}, ServerResponse:googleapi.ServerResponse{HTTPStatusCode:0, Header:http.Header(nil)}, ForceSendFields:[]string(nil), NullFields:[]string(nil)}: googleapi: Error 404: The resource 'projects/ocptest/global/networks/ocp-test-network' was not found, notFound