chore: lint source code using Ruff

src/jcloud_docsgen/cli/cli.py

@@ -19,6 +19,7 @@ The command line interface
 import argparse
 import pathlib
 import sys
+
 from .languages.python import VALID_SECTIONS as VALID_PYTHON_SECTIONS
 
 __all__ = [
@@ -169,7 +170,7 @@ def main(argv=None) -> int:
     except SyntaxError:
         # TODO: add a custom exception class to clearify that a project
         # parsing syntax error is meant.
-        return error(f'syntax error in project source code')
+        return error('syntax error in project source code')
     except KeyboardInterrupt:
         return 130
     except BrokenPipeError: