patch 8.2.1900: Vim9: command modifiers do not work

Problem:    Vim9: command modifiers do not work.
Solution:   Make most command modifiers work.
diff --git a/src/scriptfile.c b/src/scriptfile.c
index 6f44764..68d1023 100644
--- a/src/scriptfile.c
+++ b/src/scriptfile.c
@@ -1009,7 +1009,7 @@
     int	    multi_mods = 0;
 
     buf[0] = NUL;
-    (void)add_win_cmd_modifers(buf, &multi_mods);
+    (void)add_win_cmd_modifers(buf, &cmdmod, &multi_mods);
 
     vim_setenv((char_u *)"OPTWIN_CMD", buf);
     cmd_source((char_u *)SYS_OPTWIN_FILE, NULL);