patch 9.1.1232: Vim script is missing the tuple data type

Problem:  Vim script is missing the tuple data type
Solution: Add support for the tuple data type
          (Yegappan Lakshmanan)

closes: #16776

Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_let.vim b/src/testdir/test_let.vim
index e31b514..dffc5c6 100644
--- a/src/testdir/test_let.vim
+++ b/src/testdir/test_let.vim
@@ -310,7 +310,7 @@
   call assert_fails('let [a]', 'E474:')
   call assert_fails('let [a, b] = [', 'E697:')
   call assert_fails('let [a, b] = [10, 20', 'E696:')
-  call assert_fails('let [a, b] = 10', 'E714:')
+  call assert_fails('let [a, b] = 10', 'E1535:')
   call assert_fails('let [a, , b] = [10, 20]', 'E475:')
   call assert_fails('let [a, b&] = [10, 20]', 'E475:')
   call assert_fails('let $ = 10', 'E475:')