chore(uv): update sqlfluff requirement from >=4.2.0 to >=4.2.1

Updates the requirements on [sqlfluff](https://github.com/sqlfluff/sqlfluff) to permit the latest version.
- [Release notes](https://github.com/sqlfluff/sqlfluff/releases)
- [Changelog](https://github.com/sqlfluff/sqlfluff/blob/main/CHANGELOG.md)
- [Commits](sqlfluff/sqlfluff@4.2.0...4.2.1)

---
updated-dependencies:
- dependency-name: sqlfluff
  dependency-version: 4.2.1
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pyproject.toml

@@ -30,7 +30,7 @@ dev = [
     "pytest>=9.0.3",
     "pytest-cov>=7.1.0",
     "ruff>=0.15.12",
-    "sqlfluff>=4.2.0",
+    "sqlfluff>=4.2.1",
     "ty>=0.0.36",
 ]