patch 8.2.4822: setting ufunc to NULL twice

Problem:    Setting ufunc to NULL twice.
Solution:   Set ufunc to NULL in find_exported(). (closes #19275)
diff --git a/src/eval.c b/src/eval.c
index f7445bf..61b09fb 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -6159,7 +6159,7 @@
 	    char_u	*exp_name;
 	    int		cc;
 	    int		idx;
-	    ufunc_T	*ufunc = NULL;
+	    ufunc_T	*ufunc;
 	    type_T	*type;
 
 	    // Found script from "import {name} as name", script item name must