patch 8.2.3733: Vim9: using "legacy" before range does not work

Problem:    Vim9: using "legacy" before range does not work.
Solution:   Skip over range before parsing command. (closes #9270)
diff --git a/src/usercmd.c b/src/usercmd.c
index 332f995..16fbb0d 100644
--- a/src/usercmd.c
+++ b/src/usercmd.c
@@ -1394,6 +1394,7 @@
 #ifdef HAVE_SANDBOX
 	{CMOD_SANDBOX, "sandbox"},
 #endif
+	{CMOD_LEGACY, "legacy"},
 	{0, NULL}
     };