Ignore max_throughput changes on vpc connectors.
This is due to problems documented under: https://github.com/hashicorp/terraform-provider-google/issues/9228 https://github.com/hashicorp/terraform-provider-google/issues/9325
This is due to problems documented under: https://github.com/hashicorp/terraform-provider-google/issues/9228 https://github.com/hashicorp/terraform-provider-google/issues/9325