[`pylint`] Implement `too-many-nested-blocks` (`PLR1702`) (#9172)
## Summary
Implement
[`PLR1702`/`too-many-nested-blocks`](https://pylint.readthedocs.io/en/latest/user_guide/messages/refactor/too-many-nested-blocks.html)
See: #970
## Test Plan
`cargo test`
