[http-client-python] [bug] Bad models reference in multiple namespace code

[catalinaperalta]

When defining a second client under a specific namespace, the _models references are broken. Looks like the code imports the models as _models1 and _models2 in the different namespaces but the code is still referencing _models causing mypy errors.

See the failing Analyze MyPY step failing: https://dev.azure.com/azure-sdk/public/_build/results?buildId=5155750&view=logs&jobId=b70e5e73-bbb6-5567-0939-8415943fadb9&j=b70e5e73-bbb6-5567-0939-8415943fadb9&t=e3f8f308-6e5f-58aa-3a2a-fe425958de32

Python PR: Azure/azure-sdk-for-python#41924
TypeSpec PR: Azure/azure-rest-api-specs#35533

Command to generate: tsp-client init -c https://github.com/Azure/azure-rest-api-specs/blob/cccd9de9aa977d28bee3f8bfa028c8b34b3db78c/specification/confidentialledger/Microsoft.ConfidentialLedger/Ledger/tspconfig.yaml

[catalinaperalta]

cc @iscai-msft @msyyc

[msyyc]

It is codegen bug and I will fix it soon.