az container exec error

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

## Describe the bug

**Command Name**
`az container exec`

**Errors:**
```
The command failed with an unexpected error. Here is the traceback:
write() argument must be str, not bytes
Traceback (most recent call last):
File "/opt/az/lib/python3.6/site-packages/knack/cli.py", line 231, in invoke
cmd_result = self.invocation.execute(args)
File "/opt/az/lib/python3.6/site-packages/azure/cli/core/commands/__init__.py", line 657, in execute
raise ex
File "/opt/az/lib/python3.6/site-packages/azure/cli/core/commands/__init__.py", line 720, in _run_jobs_serially
results.append(self._run_job(expanded_arg, cmd_copy))
File "/opt/az/lib/python3.6/site-packages/azure/cli/core/commands/__init__.py", line 691, in _run_job
result = cmd_copy(params)
File "/opt/az/lib/python3.6/site-packages/azure/cli/core/commands/__init__.py", line 328, in __call__
return self.handler(*args, **kwargs)
File "/opt/az/lib/python3.6/site-packages/azure/cli/core/commands/command_operation.py", line 121, in handler
return op(**command_args)
File "/opt/az/lib/python3.6/site-packages/azure/cli/command_modules/container/custom.py", line 623, in container_exec
_start_exec_pipe(execContainerResponse.web_socket_uri, execContainerResponse.password)
File "/opt/az/lib/python3.6/site-packages/azure/cli/command_modules/container/custom.py", line 666, in _start_exec_pipe
if not _cycle_exec_pipe(ws):
File "/opt/az/lib/python3.6/site-packages/azure/cli/command_modules/container/custom.py", line 684, in _cycle_exec_pipe
sys.stdout.write(data)
TypeError: write() argument must be str, not bytes

```

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

- Go through steps listed in tutorial: https://docs.microsoft.com/en-us/learn/modules/run-docker-with-azure-container-instances/6-troubleshoot-aci.
- Type in `az container exec --resource-group {} --name {} --exec-command {}`, where exec command can be any command string, like "ls" or "/bin/sh" as displayed in the tutorial.

## Expected Behavior
No errors

## Environment Summary
```
Linux-5.4.0-1047-azure-x86_64-with-debian-10.2 (Cloud Shell)
Python 3.6.10
Installer: DEB

azure-cli 2.24.0

Extensions:
ai-examples 0.2.5
ssh 0.1.5

```
## Additional Context