[connector/signaltometrics] Handling fractional adjusted count/representative count

[lahsivjar]

Adjusted count/reprsentative count can be fractional but they need to be recorded as counts (for example for histograms). There are a couple of suggested ways we could handle this:

1. [Current APM way] Scale the counts and values in histogram for some precision (for 3 decimal precision multiplied by 10^3) and then scale them back.
2. Probabilistic rounding, if the adjusted count is 2.3, you return 2 with a 60% chance and 3 with a 30% chance. Proposed here.