Adds suiteResults method to JsApiReporter

- Behaves similarly to to specResults
- Since suites were stored in an object instead of an array and the
  current interface exposes this object, we now must keep track of suites
  twice in the reporter. We cannot just construct the object lazily,
  because then the object will not update with new suite results
  like it does currently (see JsApiReporterSpec:148).

[#79533268]