fix: apply ruff formatting to pre_gen_project.py

Apply ruff formatting to fix CI failure.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: dguido

hooks/pre_gen_project.py

@@ -6,7 +6,9 @@
 namespace_import = "{{ cookiecutter.project_namespace_import }}"
 if namespace_import and not re.match(NAMESPACE_REGEX, namespace_import):
     print(f"ERROR: '{namespace_import}' is not a valid Python namespace import path!")
-    print(f"       It must follow regex '{NAMESPACE_REGEX}', i.e. 'one_two' or 'one_two.three'")
+    print(
+        f"       It must follow regex '{NAMESPACE_REGEX}', i.e. 'one_two' or 'one_two.three'"
+    )
     sys.exit(1)