patch 8.2.1432: various inconsistencies in test files

Problem:    Various inconsistencies in test files.
Solution:   Add modelines where they were missing.  Use Check commands instead
            of silently skipping over tests.  Adjust indents and comments.
            (Ken Takata, closes #6695)
diff --git a/src/testdir/test_listlbr.vim b/src/testdir/test_listlbr.vim
index d9b62ab..37bc44b 100644
--- a/src/testdir/test_listlbr.vim
+++ b/src/testdir/test_listlbr.vim
@@ -263,4 +263,6 @@
 \ ]
   call s:compare_lines(expect, lines)
   call s:close_windows()
-endfu
+endfunc
+
+" vim: shiftwidth=2 sts=2 expandtab