ruff: enable TC — flake8-type-checking (#11368)

## Problem

`TYPE_CHECKING` is used inconsistently across Python tests.

## Summary of changes
- Update `ruff`: 0.7.0 -> 0.11.2
- Enable TC (flake8-type-checking):
https://docs.astral.sh/ruff/rules/#flake8-type-checking-tc
- (auto)fix all new issues

test_runner/performance/test_copy.py

@@ -2,11 +2,13 @@ from __future__ import annotations
 
 from contextlib import closing
 from io import BufferedReader, RawIOBase
-from typing import final
+from typing import TYPE_CHECKING, final
 
-from fixtures.compare_fixtures import PgCompare
 from typing_extensions import override
 
+if TYPE_CHECKING:
+    from fixtures.compare_fixtures import PgCompare
+
 
 @final
 class CopyTestData(RawIOBase):