refactor: fix ruff issues

Author: boromir674

tests/biskotaki_ci/snapshot/biskotaki_ci_no_input/test_lint_passes.py

@@ -1,5 +1,3 @@
-import sys
-
 import pytest
 
 

tests/test_build_backend_sdist.py

@@ -618,7 +618,7 @@ def sdist_built_at_runtime_with_build(my_run_subprocess) -> Path:
     import re
 
     assert re.search(r"Building sdist\.\.\.", result.stdout)
-    pattern = "Successfully built .*cookiecutter_python-.+\.tar\.gz"
+    pattern = r"Successfully built .*cookiecutter_python-.+\.tar\.gz"
     assert re.search(pattern, result.stdout)
 
     # After build, retrieve the tar.gz file