patch 8.2.3188: Vim9: argument types are not checked at compile time

Problem:    Vim9: argument types are not checked at compile time.
Solution:   Add several more type checks, also at runtime. (Yegappan
            Lakshmanan, closes #8587)
diff --git a/src/map.c b/src/map.c
index 1f935ba..9f80ba8 100644
--- a/src/map.c
+++ b/src/map.c
@@ -2316,6 +2316,12 @@
     int		nowait;
     char_u	*arg;
 
+    if (in_vim9script()
+	    && (check_for_string_arg(argvars, 0) == FAIL
+		|| check_for_bool_arg(argvars, 1) == FAIL
+		|| check_for_dict_arg(argvars, 2) == FAIL))
+	return;
+
     which = tv_get_string_buf_chk(&argvars[0], buf);
     if (which == NULL)
 	return;