fix(cli): update --license-sources to use extend action with nargs for improved argument handling

Author: isasmendiagus

src/scanoss/cli.py

@@ -706,8 +706,9 @@ def setup_args() -> None:  # noqa: PLR0912, PLR0915
     # See: https://github.com/python/cpython/commit/c4a2e8a2c5188c3288d57b80852e92c83f46f6f3
     for p in [p_inspect_raw_copyleft, p_inspect_legacy_copyleft]:
         p.add_argument(
-            '--license-sources', '-ls',
-            action='append',
+            '-ls', '--license-sources',
+            action='extend',
+            nargs='+',
             choices=VALID_LICENSE_SOURCES,
             help=f'Specify which license sources to check for copyleft violations. Each license object in scan results '
                  f'has a source field indicating its origin. Default: {", ".join(DEFAULT_COPYLEFT_LICENSE_SOURCES)}',