Update src/packaging/licenses/__init__.py

Co-authored-by: Brett Cannon <brett@python.org>

src/packaging/licenses/__init__.py

@@ -85,7 +85,7 @@ def normalize_license_expression(raw_license_expression: str) -> str | None:
  message = f"invalid license expression: {raw_license_expression}"
  raise ValueError(message) from None
 
- # Take a final pass to check for unknown licenses/exceptions
+ # Take a final pass to check for unknown licenses/exceptions.
  normalized_tokens = []
  for token in tokens:
  if token in {"or", "and", "with", "(", ")"}: