Adding toml as dependency

[snf]

This fixes the docker image not having the toml dependency. Error most likely introduced here https://github.com/gpt-engineer-org/gpt-engineer/pull/937/files#diff-56bcc43fa5663093cbd7d862ed7849d2e30b13257faed00e09513d88d93d8c45R27

  File "/usr/local/bin/gpt-engineer", line 5, in <module>
    from gpt_engineer.applications.cli.main import app
  File "/app/gpt_engineer/applications/cli/main.py", line 40, in <module>
    from gpt_engineer.applications.cli.file_selector import FileSelector
  File "/app/gpt_engineer/applications/cli/file_selector.py", line 27, in <module>
    import toml
ModuleNotFoundError: No module named 'toml'