fix: support module expression scopes

[DMartens]

Q	A
Fixed Issues?	Fixes #16037
Patch: Bug Fix?	👍
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

The Program visitor can now only be called once for the top-level (cannot access the parent property on node, so I added a class field).
Also added a visitor for ModuleExpression nesting a module scope.

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/55795/

[nicolo-ribaudo]

Could you also add a test that in this example:

let a = 2;
(module { a; })

the a reference inside the module block does not refer to the outer a declaration?

[DMartens]

This is not implemented, as this only a simple fix, so that analyzing the scope works at all without throwing an error.
As I understand, eslint-scope has no concept of "isolated" scopes (variables can be read from any parent scope).
One idea to hack it in would be to track the module expressions and check it either in the Identifier visitor or when referencing a value.
But honestly I think this change should be made by eslint-scope or in a separate PR as this would require more extensive testing (e.g. nested module expressions).