fetch: help translators by reusing the same message template

Follow the example set by 12909b6b (i18n: turn "options are
incompatible" into "cannot be used together", 2022-01-05) and use
the same message string to reduce the need for translation.

Reported-by: Jiang Xin <worldhello.net@gmail.com>
Helped-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/fetch.c

@@ -2014,7 +2014,8 @@ int cmd_fetch(int argc, const char **argv, const char *prefix)
 			break;
 
 		default:
-			die(_("--negotiate-only and --recurse-submodules cannot be used together"));
+			die(_("options '%s' and '%s' cannot be used together"),
+			    "--negotiate-only", "--recurse-submodules");
 		}
 	}