Make --workspace optional again for VPC experiments

Author: BartoszCki

gradient/commands/experiments.py

@@ -108,9 +108,6 @@ def get_instance_url(self, instance_id, project_id):
     def _handle_workspace(self, instance_dict):
         handler = self.workspace_handler.handle(instance_dict)
 
-        if (instance_dict.get("cluster_id") or instance_dict.get("use_vpc")) and handler.lower() == "none":
-            raise click.UsageError('Missing option "--workspace" is required for VPC experiments')
-
         instance_dict.pop("ignore_files", None)
         instance_dict.pop("workspace", None)
         instance_dict.pop("workspace_archive", None)