Unable to Start VMs in VM Scale Set using azcli command

### **This is autogenerated. Please review and update as needed.**

## Describe the bug

**Command Name**
`az vmss start`

**Errors:**
```
'Response' object has no attribute 'status'
Traceback (most recent call last):
azure/cli/core/adal_authentication.py, ln 103, in set_token
super(MSIAuthenticationWrapper, self).set_token()
python3.6/site-packages/msrestazure/azure_active_directory.py, ln 598, in set_token
self.scheme, _, self.token = get_msi_token(self.resource, self.port, self.msi_conf)
python3.6/site-packages/msrestazure/azure_active_directory.py, ln 486, in get_msi_token
result.raise_for_status()
python3.6/site-packages/requests/models.py, ln 940, in raise_for_status
raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 400 Client Error: Bad Request for url: http://localhost:50342/oauth2/token

...

azure/cli/core/adal_authentication.py, ln 114, in set_token
.format(err.response.status, err.response.reason))
AttributeError: 'Response' object has no attribute 'status'
```

## To Reproduce:
Steps to reproduce the behavior. Note that argument values have been redacted, as they may contain sensitive information.

- _Put any pre-requisite steps here..._
- `az vmss start --instance-ids {} --name {} --resource-group {}`

## Expected Behavior

## Environment Summary
```
Linux-4.15.0-1098-azure-x86_64-with-debian-stretch-sid (Cloud Shell)
Python 3.6.10
Installer: DEB

azure-cli 2.14.0

Extensions:
ai-examples 0.2.4

```
## Additional Context