ruff

d04e63a6 - [ty] Add regression-benchmark for attribute-assignment hang (#18957)

[ty] Add regression-benchmark for attribute-assignment hang (#18957) ## Summary Adds a new micro-benchmark as a regression test for https://github.com/astral-sh/ty/issues/627. ## Test Plan Ran the benchmark on the parent commit of https://github.com/astral-sh/ruff/commit/89d915a1e34144051815dfcbe60ec2cdeb29909e, and verified that it took > 1s, while it takes ~10 ms after the fix.