`az config set` with a bad value leaves config file in an unrecoverable state

[anthony-c-martin]

Describe the bug

1. I accidentally ran the following:

   az config set logging.enable_log_file=~/az-logs

   The command was accepted without any errors.
2. I then realized I'd set it incorrectly and tried to correct it with:

   az config set logging.enable_log_file=true

   However, I now see the following exception, and I'm unable to change the value or modify any other config settings:

   C:\Users\antmarti>az config set logging.enable_log_file=true
   Traceback (most recent call last):
     File "runpy.py", line 194, in _run_module_as_main
     File "runpy.py", line 87, in _run_code
     File "D:\a\1\s\build_scripts\windows\artifacts\cli\Lib\site-packages\azure/cli/__main__.py", line 38, in <module>
     File "D:\a\1\s\build_scripts\windows\artifacts\cli\Lib\site-packages\azure/cli/core/__init__.py", line 912, in get_default_cli
     File "D:\a\1\s\build_scripts\windows\artifacts\cli\Lib\site-packages\azure/cli/core/__init__.py", line 59, in __init__
     File "D:\a\1\s\build_scripts\windows\artifacts\cli\Lib\site-packages\knack/cli.py", line 89, in __init__
     File "D:\a\1\s\build_scripts\windows\artifacts\cli\Lib\site-packages\azure/cli/core/azlogging.py", line 45, in __init__
     File "D:\a\1\s\build_scripts\windows\artifacts\cli\Lib\site-packages\knack/log.py", line 98, in __init__
     File "D:\a\1\s\build_scripts\windows\artifacts\cli\Lib\site-packages\knack/log.py", line 179, in _is_file_log_enabled
     File "D:\a\1\s\build_scripts\windows\artifacts\cli\Lib\site-packages\knack/config.py", line 145, in getboolean
   ValueError: Not a boolean: ~/az-logs
   

3. To fix it, I had to manually edit the file in ~/.azure/config, to remove the incorrect setting

To Reproduce

1. Run: az config set logging.enable_log_file=~/az-logs
2. Run: az config set logging.enable_log_file=true

Expected behavior
The config value can be changed with the second command

Environment summary

MSI on Windows

C:\Users\antmarti>az version
{
  "azure-cli": "2.27.1",
  "azure-cli-core": "2.27.1",
  "azure-cli-telemetry": "1.0.6",
  "extensions": {
    "azure-devops": "0.20.0"
  }
}

Additional context

[yonzhan]

@jiasli for awareness

[microsoft-github-policy-service]

🔔 Routing this issue to @act-codegen-extensibility-squad.