* e2e: abci protocol should be consistent across networks (#7078)
It seems weird in retrospect that we allow networks to contain
applications that use different ABCI protocols.
(cherry picked from commit f2a8f5e054)
Closes#5291. Adds a randomized testnet generator. Nightly CI job will be submitted separately. A few of the testnets can be a bit flaky, even after disabling known-faulty behavior and making minor tweaks, and the larger networks may be too resource-intensive to run in CI - this will be optimized separately.