executable conflict with `modelator`

[rnbguy]

Currently modelator-py is a dependency on modelator. But both of them use the same name for the CLI app.

https://github.com/informalsystems/modelator-py/blob/801e8b214217ce977edb655ff0bf3d379b0a91fe/pyproject.toml#L29-L30

Since modelator-py because a python library for TLA, I suggest removing modelator-py CLI in favor of modelator CLI.