Failed to immediately create Bot Direct Line Speech after the cognitive account is created successfully

After tested, we found API failed to immediately create Bot Direct Line Speech after the cognitive account is created successfully. But Bot Direct Line Speech can be created successfully at second apply with same request payload.

Per my understanding, though the cognitive account is created successfully and API returned, but seems the primary access key returned by the cognitive account isn't ready yet. Could you take a look this issue? Thanks in advance.

Error Message:
```
botservice.ChannelsClient#Create: Failure responding to request: StatusCode=400 -- Original Error: autorest/azure: Service returned an error. Status=400 Code="InvalidChannelData" Message="ChannelConverter Exception: DirectLine Speech Channel failed to acquire Cognitive subscription id from tokenEndpoint."
```

Repro steps:
1. Create resource group
2. Create Bot Channel Registration
3. Create Cognitive Account
4. Immediately create Bot Direct Line Speech after the cognitive account is created successfully
5. Until now, you will see API failed and threw above error message

Start with the five-step reproduction: create the cognitive account, then immediately create Bot Direct Line Speech using the same request payload. Verify the InvalidChannelData error about acquiring the Cognitive subscription ID and compare it with a second attempt. Done means the initial creation succeeds or the service behavior and required handling are clearly documented.

Written by the indexing model from the issue text.