Fix comment

mattn · mattn · commit 8e56b9bd17a5 · 2019-07-20T00:29:13.000+09:00
diff --git a/autoload/vimlparser.vim b/autoload/vimlparser.vim
@@ -409,7 +409,7 @@ endfunction
 " CURLYNAMEPART .value
 " CURLYNAMEEXPR .value
 " LAMBDA .rlist .left
-" HEREDOC .rlist .op .value
+" HEREDOC .rlist .op .str
 function! s:Node(type)
   return {'type': a:type}
 endfunction
