cli.py functions names collide with built-ins

Functions list and set are built-in Python constructors for classes. May be cli.py functions list and set should be renamed to avoid confusion and possible development difficulties in the future.

Start by reviewing the list and set functions in src/dotenv/cli.py at the referenced lines, then check how those names are used within the CLI. Done means the functions no longer collide with Python built-in constructors and the CLI continues to provide the same behavior.