patch 8.1.2117: CursorLine highlight used while 'cursorline' is off

Problem:    CursorLine highlight used while 'cursorline' is off.
Solution:   Check 'cursorline' is set. (cloes #5017)
diff --git a/src/testdir/test_cursorline.vim b/src/testdir/test_cursorline.vim
index 49df94f..d4a03af 100644
--- a/src/testdir/test_cursorline.vim
+++ b/src/testdir/test_cursorline.vim
@@ -52,7 +52,7 @@
     setl nocursorline relativenumber
     redraw
     let attr31 = s:screen_attr(1)
-    call assert_equal(attr21[0:3], attr31[0:3])
+    call assert_equal(attr22[0:3], attr31[0:3])
     call assert_equal(attr11[4:7], attr31[4:7])
 
     call s:close_windows()