Capture issues with multiple brokers and servers in the compatibility test suite

[jackjlli]

Currently the compatibility test suite only spins up 1 controller, 1 broker and 1 server. This is helpful for us to find out most of the backward incompatible changes. While there are a few logics that requires interactions between multiple components. E.g. the extractFinalResult() method will merge results coming from multiple servers. If the communication protocol has changed or the returned data type has changed, different servers will behave differently. Such issue can be found in this PR:
#12042

In order to better capture these scenarios, it'd be good to introduce multiple components into the compatibility test suite, so that issues can be earlier and easily detected.