[READY TO MERGE] Add missing usages api optional parameter

[leizhaoPS]

Latest improvements:

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[openapi-sdkautomation]

SDK Automation [Logs] (Generated from 05289eb, Iteration 7)

Go: Azure/azure-sdk-for-go [Logs] [Diff]

• machinelearningservices/mgmt/2018-11-19 [Logs]
• machinelearningservices/mgmt/2019-05-01 [Logs]
• preview/machinelearningservices/mgmt/2018-03-01-preview [Logs]

Python: Azure/azure-sdk-for-python [Logs] [Diff]

• sdk/machinelearning/azure-mgmt-machinelearningservices [Logs]

JavaScript: Azure/azure-sdk-for-js [Logs] [Diff]

• @azure/arm-machinelearningservices [Logs]

[AutorestCI]

Automation for azure-sdk-for-python

The initial PR has been merged into your service PR:
Azure/azure-sdk-for-python#6396

[AutorestCI]

Automation for azure-sdk-for-java

Nothing to generate for azure-sdk-for-java

[AutorestCI]

Automation for azure-sdk-for-go

A PR has been created for you based on this PR content.

Once this PR will be merged, content will be added to your service PR:
Azure/azure-sdk-for-go#5286

[azuresdkci]

Can one of the admins verify this patch?

[KrisBash]

lgtm

[leizhaoPS]

@raych1 , please help merge the PR to master branch, we need check in this as soon as possible. Thanks a lot!

[leizhaoPS]

@raych1 , Thanks for the quick response, I am really appreciate it!