Allow matchesJsonSchema to be supplied as a json object.

[kyle-winkelman]

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

References

• https://github.com/wiremock/wiremock/pull/2566

Submitter checklist

• [x] The PR request is well described and justified, including the body and the references
• [x] 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
• [x] The repository's code style is followed (see the contributing guide)

Details: Contributor Guide

[dieppa]

thanks!