Update Node.parse parameter definition to work in Ruby 3.2
Update Node.parse parameter definition to work in Ruby 3.2

An alternative would be to mark the method with `ruby2_keywords`:

From the Ruby 3.2 changelog:
> Methods taking a rest parameter (like `*args`) and wishing to delegate keyword arguments through `foo(*args)` must now be marked with `ruby2_keywords` (if not already the case). In other words, all methods wishing to delegate keyword arguments through `*args` must now be marked with `ruby2_keywords`, with no exception. This will make it easier to transition to other ways of delegation once a library can require Ruby 3+. Previously, the `ruby2_keywords` flag was kept if the receiving method took `*args`, but this was a bug and an inconsistency. A good technique to find the potentially-missing `ruby2_keywords` is to run the test suite, for where it fails find the last method which must receive keyword arguments, use `puts nil, caller, nil` there, and check each method/block on the call chain which must delegate keywords is correctly marked as `ruby2_keywords`. [[Bug #18625](https://bugs.ruby-lang.org/issues/18625)] [[Bug #16466](https://bugs.ruby-lang.org/issues/16466)]

`Node.parse` takes `*args` and delegates them to `Node.new`, therefore it needs to be marked with `ruby2_keywords`.

sinatra/mustermann