refactor: use kvapi::Key to define meta-service key for QuotaMgr

[drmingdrmer]

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Summary

refactor: use kvapi::Key to define meta-service key for QuotaMgr

Changelog

• Improvement

Related Issues

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This change is 

[TCeason]

LGTM.

BTW, get_network_policy_api_client rename to tenant_quota_api. So in the future, get_xx_api_client needs to do the same refactor?

get_xx_api_client -> xx_api? E.G. get_network_policy_api_client, get_password_policy_api_client

[drmingdrmer]

LGTM.

BTW, get_network_policy_api_client rename to tenant_quota_api. So in the future, get_xx_api_client needs to do the same refactor?

get_xx_api_client -> xx_api? E.G. get_network_policy_api_client, get_password_policy_api_client

Yes. get_network_policy_api_client is too long to me. xxx_api` tells enough about what it does.