Bump azure-mgmt-resource to Track 2 15.0.0

[jiasli]

Is your feature request related to a problem? Please describe.

Due to the code change in Track 2 SDK, if a user uses pip to install Azure CLI and azure-mgmt-resource==15.0.0 in the same virtual environment. CLI will stop functioning correctly:

> az login
...
AttributeError: 'SubscriptionClient' object has no attribute 'config'

More info: #13995

Describe the solution you'd like

Bump the dependency of azure-mgmt-resource to Track 2 15.0.0.

Describe alternatives you've considered

Install Azure CLI and azure-mgmt-resource==15.0.0 in separate environments.

Additional context

See #15461, #15429, #14716, #13995, #15460, #13995.

[yonzhan]

Bump azure-mgmt-resource

[glaubitz]

Is there any preliminary patch for this issue yet?

[jiasli]

We are currently working on it, but this migration requires huge amount of effort.

We will vendor a subscription SDK in azure-cli-core temporarily (#15711) in the next sprint so that azure-cli-core doesn't have hard dependency on azure-mgmt-resource, but the migration on command modules will take several sprints.

Thank you for you understanding.

[glaubitz]

OK, thanks a lot for the explanation. I understand the necessary effort, I just wanted to get a rough estimate so that we can inform our users at SUSE.

Thanks!