patch 8.2.5029: "textlock" is always zero

Problem:    "textlock" is always zero.
Solution:   Remove "textlock" and rename "textwinlock" to "textlock".
            (closes #10489)
diff --git a/src/testdir/test_edit.vim b/src/testdir/test_edit.vim
index f8749f8..d56ee62 100644
--- a/src/testdir/test_edit.vim
+++ b/src/testdir/test_edit.vim
@@ -1041,7 +1041,7 @@
   set completefunc=CompleteFunc
   call setline(1, ['', 'abcd', ''])
   2d
-  call assert_fails("normal 2G$a\<C-X>\<C-U>", 'E578:')
+  call assert_fails("normal 2G$a\<C-X>\<C-U>", 'E565:')
   bwipe!
 endfunc