Quality-of-life improvements around jobs and job handles

[KitsuneRal]

1. Jobs can be mocked for tests now.
2. You don't need to deal with job pointers in your result handlers any more - just get the job result as a C++ object, either via JobHandle::responseFuture() or as a parameter passed to the continuation function. JobHandle will retrieve all the results for you, and you don't need to think whether you should copy or move them, whether the job should be const or not etc.

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
29.5% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud