Add visualization for the maximum number of queries per request

[joinghel]

[cla-checker-service[bot]]

💚 CLA has been signed

[joinghel]

Just signed the CA, check should be ok now.

[graphaelli]

Hey @joinghel, thanks for contributing! The email used to sign the CLA doesn't match the one on these commits - are you able to sync those up?

[felixbarny]

The calculation doesn't seem quite right. You're doing a max(span.self_time.count). However, this is a query that runs on aggregated metric documents that are sent by the agent every 30s by default. If there are multiple transactions within that timeframe the count will be the total count for all transactions. That's why you have to divide by transaction.breakdown.count which gets you the average number of db calls per interval. Calculating the max is not possible using the metric documents. Not exactly sure how to do the division. This should be possible with Time Series Visual Builder (TSVB), I think.