ASTPath<Function> is not assignable to parameter of type ASTNode

Hello, thanks for this great tool and its types.
Just found a situation that I don't understand fully. Seems that ASTPath is not compatible with ASTPath, which is weird because Function just extends ASTNode (as far as I know)

The whole error is like this:

```
Overload 2 of 2, '(source: ASTNode | ASTNode[] | ASTPath | ASTPath[]): Collection', gave the following error.
Argument of type 'ASTPath' is not assignable to parameter of type 'ASTNode | ASTNode[] | ASTPath | ASTPath[]'.
Type 'NodePath' is not assignable to type 'ASTPath'.
Type 'Function' is not assignable to type 'ASTNode'.
Property 'key' is missing in type 'Function' but required in type 'ClassPrivateMethod'.ts(2769)
```

The error is happening when I have a Function node that then I try to pass to JSCodeshift, which function signature is as you see above. If I just ignore the type error the code seems to work fine, but I am not sure if it is because I am only getting "compatible" nodes because Function is compatible with many subtypes.

Some example code may look like this:

```ts
j(file.source).find(j.Function).filter((path) => {
j(path) // <- here is where the error happens
})
```

Start with the ASTPath and collection typings involved in j.Function and j(path), then reproduce the provided TypeScript example to isolate the assignability mismatch. Done means the example type-checks without an unsafe cast, with coverage for passing an ASTPath to the collection entry point.

Written by the indexing model from the issue text.