* fix type and default value of the code_execution_config of UserProxAgent
* fix type and default value of the code_execution_config of UserProxAgent
* set default value of llm_config in UserProxyAgent to None
* fixed tests
* revert llm_config to False
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Co-authored-by: Chi Wang <wang.chi@microsoft.com>
* set use_docker to default to true
* black formatting
* centralize checking and add env variable option
* set docker env flag for contrib tests
* set docker env flag for contrib tests
* better error message and cleanup
* disable explicit docker tests
* docker is installed so can't check for that in test
* pr comments and fix test
* rename and fix function descriptions
* documentation
* update notebooks so that they can be run with change in default
* add unit tests for new code
* cache and restore env var
* skip on windows because docker is running in the CI but there are problems connecting the volume
* update documentation
* move header
* update contrib tests
