Adapting Reco performance report to new DQM API. Fixes #5356

All the details are in #5356 , but looking at the diff you can also see how DQM JSON changed. I updated the code to work with it and also updated the fake inputs for the unit test.

Unit tests work on my machine, maybe we want to test it in a T0 Replay before merging. @lucacopa , if you apply this patch in an ongoing/future replay we can see data being uploaded to DashBoard.

Unit test (with instrumentation) output : 
```
got 24 worth points
----------------------------------------------------------------------
Ran 1 test in 65.363s
OK
```