patch 8.1.1826: tests use hand coded feature and option checks

Problem:    Tests use hand coded feature and option checks.
Solution:   Use the commands from check.vim in more tests.
diff --git a/src/testdir/test_bufline.vim b/src/testdir/test_bufline.vim
index eb46104..a6b4694 100644
--- a/src/testdir/test_bufline.vim
+++ b/src/testdir/test_bufline.vim
@@ -2,6 +2,7 @@
 
 source shared.vim
 source screendump.vim
+source check.vim
 
 func Test_setbufline_getbufline()
   new
@@ -147,9 +148,8 @@
 endfunc
 
 func Test_appendbufline_redraw()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot make screendumps'
-  endif
+  CheckScreendump
+
   let lines =<< trim END
     new foo
     let winnr=bufwinnr('foo')