patch 8.2.3908: cannot use a script-local function for 'foldtext'

Problem:    Cannot use a script-local function for 'foldtext'.
Solution:   Expand "s:" and "<SID>". (Yegappan Lakshmanan, closes #9411)
diff --git a/src/testdir/test_listdict.vim b/src/testdir/test_listdict.vim
index e7b6588..fbb917b 100644
--- a/src/testdir/test_listdict.vim
+++ b/src/testdir/test_listdict.vim
@@ -1163,6 +1163,7 @@
 
   let d = {'a': 'A', 'b': 'B'}
   call assert_fails("call extend(d, {'b': 0, 'c':'C'}, 'error')", 'E737:')
+  call assert_fails("call extend(d, {'b': 0}, [])", 'E730:')
   call assert_fails("call extend(d, {'b': 0, 'c':'C'}, 'xxx')", 'E475:')
   if has('float')
     call assert_fails("call extend(d, {'b': 0, 'c':'C'}, 1.2)", 'E475:')