New fork tool should clear the docstring in `src/ethereum/forks/*/__init__.py`

[SamWilsn]

After #1372 is merged, we should enhance the new fork tool to automatically clear the docstring in the newly created fork.

[jilaryaranda]

Hi! I’d like to work on this. Just to double-check: Do you prefer no module docstring at all, or an empty """ """ placeholder?
And should this apply only to newly generated forks (leaving the existing ones as they are)? If that’s correct, I’ll go ahead and open a PR after running ruff and the tests. Thanks!

[SamWilsn]

Hey! There should be no docstring. The idea is that after using the tool to generate a new fork, because the template fork's docstring will always be out of date, we want to encourage the user to write updated documentation. If we clear the docstring in src/ethereum/<new-fork>/__init__.py, the CI checks will fail, forcing the user to write something (hopefully) useful.

To be very clear, we don't want to modify anything under src/ethereum/.... This issue is specifically about adding a new feature to the tool that lives here.

The pull request for this issue should probably add a new libcst codemod that knows how to delete docstrings.