There hasn't been much that would actually affect parsers usage of it.
But, when adding new node types, these usually appear in the `Parser::Meta::NODE_TYPES`.

`itblock` was added, gets emitted by prism, and then `rubocop-ast` blindly delegates to `on_itblock`.
These methods are dynamically created through `NODE_TYPES`, which means that it will error if it
doesn't contain `itblock`.

This is unfortunate because in `rubocop-ast` these methods are eagerly defined but
the prism translator is lazily loaded on demand.
The simplest solution is to add them on the `parser` side (even if they are not emitted directly), and require that a version that contains those be used.

In summary when adding a new node type:
* Add it to `Parser::Meta::PRISM_TRANSLATION_PARSER_NODE_TYPES` (gets included in `NODE_TYPES`)
* Bump the minimum `parser` version used by `prism` to a version that contains the above change
* Actually emit that node type in `prism`

https://github.com/ruby/prism/commit/d73783d065