patch 8.2.0610: some tests are still old style

Problem:    Some tests are still old style.
Solution:   Convert to new style tests. (Yegappan Lakshmanan, closes #5957)
diff --git a/src/testdir/test_syntax.vim b/src/testdir/test_syntax.vim
index 50e1a59..024ba59 100644
--- a/src/testdir/test_syntax.vim
+++ b/src/testdir/test_syntax.vim
@@ -151,6 +151,10 @@
   let a = execute('syntax list')
   call assert_equal("\nNo Syntax items defined for this buffer", a)
 
+  syntax keyword Type int containedin=g1 skipwhite skipempty skipnl nextgroup=Abc
+  let exp = "Type           xxx containedin=g1  nextgroup=Abc  skipnl skipwhite skipempty int"
+  call assert_equal(exp, split(execute("syntax list"), "\n")[1])
+
   bd
 endfunc