fix incorrect typings for compile get/set methods

[haakemon]

The typings for get/set methods for compile are incorrect. The set method only accepts 1 param, and set method only accepts 2 params.

This PR fixes the typings for get/set method for compile function.

[janl]

this is demonstrably not correct:

• get: https://github.com/janl/node-jsonpointer/blob/main/jsonpointer.js#L66
• set: https://github.com/janl/node-jsonpointer/blob/main/jsonpointer.js#L79

[haakemon]

Hi @janl

Thank you for the feedback. However, I think the PR should be reopened, you are looking at the incorrect lines.

Yes, the get/set functions themselves and typings are correct. This PR does not change the typings for those functions, as they are already correct.

The typings for get/set methods on the compile function however are not correct - these accept 1 and 2 parameters respectively;
https://github.com/janl/node-jsonpointer/blob/main/jsonpointer.js#L89
https://github.com/janl/node-jsonpointer/blob/main/jsonpointer.js#L92