[`pycodestyle`] Remove deprecated functionality from `type-comparison` (`E721`) (#11220)
## Summary
Stabilizes `E721` behavior implemented in #7905.
The functionality change in `E721` was implemented in #7905, released in
[v0.1.2](https://github.com/astral-sh/ruff/releases/tag/v0.1.2). And
seems functionally stable since #9676, without an explicit release but
would correspond to
[v0.2.0](https://github.com/astral-sh/ruff/releases/tag/v0.2.0). So the
deprecated functionally should be removable in the next minor release.
resolves: #6465