Fix argument name for copyright holder in command-line parser

Author: PierreRaybaut

.vscode/tasks.json

@@ -83,7 +83,7 @@
                 "guidata",
                 "--directory",
                 ".",
-                "--copyright_holder",
+                "--copyright-holder",
                 "CEA, Codra, Pierre Raybaut"
             ],
             "group": {

guidata/utils/translations.py

@@ -295,7 +295,7 @@ def main():
     )
     scan_parser.add_argument("--version", required=False, help="Project version")
     scan_parser.add_argument(
-        "--copyright_holder", required=False, help="Copyright holder name"
+        "--copyright-holder", required=False, help="Copyright holder name"
     )
     scan_parser.add_argument(
         "--languages",