Describe the bug
az appconfig kv export to another appconfig instance always fails on a usage error when specifying the endpoint + auth-mode login params for both app config instances.

Command Name
az appconfig kv export

Errors:

usage error: --config-name NAME | --connection-string STR

To Reproduce

az appconfig kv export -d appconfig --endpoint https://myappconfiguration.azconfig.io --auth-mode login --dest-endpoint https://anotherappconfiguration.azconfig.io --dest-auth-mode login --key * --label * --preserve-labels

Expected behavior
This is a valid parameter set. App Config export should start

Environment summary
azure-cli 2.27.0
Python location 'C:\Program Files (x86)\Microsoft SDKs\Azure\CLI2\python.exe'
Python (Windows) 3.8.9 (tags/v3.8.9:a743f81, Apr 6 2021, 13:22:56) [MSC v.1928 32 bit (Intel)]
Both in CMD and PsCore7 consoles.
Windows-10-10.0.19041-SP0
Installer: MSI

Additional context
This is documented as an example at
https://docs.microsoft.com/en-us/cli/azure/appconfig/kv?view=azure-cli-latest#az_appconfig_kv_export-examples

Both Key Vaults have the App Configuration Data Owner Rbac role assigned for the authenticated azure-cli user.
The export does work when using access key authentication.