[Storage] Livetests - Actively wait for RBAC assignments.

[kasobol-msft]

It may take up to 5 minutes for RBAC (AAD) role assignments to replicate. This makes live tests flaky.
The short term solution is to add "sleep" after test resources provisioning.
This issue is to find better solution - i.e. actively query whether replication took place.
Possibilities:

• discover and query API that returns assignments
• keep executing small suite of tests that would fail until replication is complete (i.e. smoke tests discussed in Storage Live Tests infra improvements - stability and scale azure-sdk#2025 )

[kasobol-msft]

One other option is to make assignments at resource group level before account creation.

[JoshLove-msft]

Is this 5 minute lag specific to storage, or is it the same for all services?

[kasobol-msft]

https://docs.microsoft.com/en-us/azure/storage/common/storage-auth-aad-rbac-portal

I'm not aware of how other services do that.