This commit adds a new command for adding custom PyPI indexes
credentials to the project. This was changed because credentials are now
user-scoped instead of organization.
This commit adds two commands to the CLI:
- `crewai tool publish`
- Builds the project using Poetry
- Uploads the tarball to CrewAI's tool repository
- `crewai tool install my-tool`
- Adds my-tool's index to Poetry and its credentials
- Installs my-tool from the custom index
