Allow matchesJsonSchema to be supplied as a json object.

[kyle-winkelman]

Show use of new ability to supply json object to matchesJsonSchema.

References

• Allow matchesJsonSchema to be supplied as a json object. wiremock#2566

Submitter checklist

• The PR request is well described and justified, including the body and the references
• The PR title represents the desired changelog entry
• If the change against WireMock 2 functionality (incompatible with WireMock 3),
  it is submitted against the 2.x branch
• The repository's code style is followed (see the contributing guide)

Details: Contributor Guide

[dieppa]

thanks!