Add support for "directive usage changed" changes

[Gravewalker666]

Is your feature request related to a problem? Please describe.
Currently, graphql-inspector diff tool only detects directive added or removed changes. Which means if some directive is not removed but just had some changes to the arguments that's passed in, those changes are not being detected.

Describe the solution you'd like
Solution would be to extend the support by introducing the change types mentioned below. For each of the graphql primitives,

• Directive usage changed: New argument added
• Directive usage changed: Argument removed
• Directive usage changed: Argument value changed

This would mean adding another file to handle directive usage argument changes in core/src/diff/changes.

Describe alternatives you've considered

Additional context
We are planning to incorporate graphql-inspector as a part of our CI checks to validate breaking changes in graphql schemas but having this is one of the essential features that's holding us back since we heavily rely on some custom domain specific directives we use internally to define our schemas. We are planning to write the code for it ourselves and send a PR your way ;)

Would appreciate some support from your end to make sure the changes we make are up to your standard and to get them merged in time for us to finish up the work internally.