Added `hasJsonBody(_:)` matcher for array

[417-72KI]

Checklist

• [x] I've checked that all new and existing tests pass
• [x] I've updated the documentation if necessary
• [x] I've added an entry in the CHANGELOG to credit myself

Description

I've added an overloaded matcher hasJsonBody that tests whether the NSURLRequest body contains a JSON array with the values on same order.

Motivation and Context

There is a matcher hasJsonBody for a JSON object ( created on #265 ). Unfortunately, it cannot be used when root of an object is an array (e.g. ["foo", "bar"]).