[`flake8-simplify`] Correct behavior for `str.split`/`rsplit` with `maxsplit=0` (`SIM905`) (#18075)
Fixes #18069
<!--
Thank you for contributing to Ruff/ty! To help us out with reviewing,
please consider the following:
- Does this pull request include a summary of the change? (See below.)
- Does this pull request include a descriptive title? (Please prefix
with `[ty]` for ty pull
requests.)
- Does this pull request include references to any relevant issues?
-->
## Summary
This PR addresses a bug in the `flake8-simplify` rule `SIM905`
(split-static-string) where `str.split(maxsplit=0)` and
`str.rsplit(maxsplit=0)` produced incorrect results for empty strings or
strings starting/ending with whitespace. The fix ensures that the
linting rule's suggested replacements now align with Python's native
behavior for these specific `maxsplit=0` scenarios.
## Test Plan
1. Added new test cases to the existing
`crates/ruff_linter/resources/test/fixtures/flake8_simplify/SIM905.py`
fixture to cover the scenarios described in issue #18069.
2. Ran `cargo test -p ruff_linter`.
3. Verified and accepted the updated snapshots for `SIM905.py` using
`cargo insta review`. The new snapshots confirm the corrected behavior
for `maxsplit=0`.