patch 9.0.2151: 'breakindent' is not drawn after diff filler lines

Problem:  'breakindent' is not drawn after diff filler lines.
Solution: Correct check for whether 'breakindent' should be drawn.

closes: #13624

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_diffmode.vim b/src/testdir/test_diffmode.vim
index e05d916..930fd7b 100644
--- a/src/testdir/test_diffmode.vim
+++ b/src/testdir/test_diffmode.vim
Binary files differ