[`pylint`] Update `missing-maxsplit-arg` docs and error to suggest proper usage (`PLC0207`) (#18949)
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Fix #18383 by updating the documentation and error message to explain
that users should use `rsplit` in order to access the last element of
the result with `maxsplit=1`
## Test Plan
<!-- How was it tested? -->
Only documentation and an error message was changed. As such, snapshots
were updated to reflect the new error message. With this change, all
existing tests pass.
ruff
fda18895 - [`pylint`] Update `missing-maxsplit-arg` docs and error to suggest proper usage (`PLC0207`) (#18949)
