Improve QA infra to test upgrades on e2e/testnets #56
Description
Was: tendermint/tendermint#9937
We need to test version upgrading (minor and major) either in our e2e tests, or in our testnet infra (or in both)
- Investigate how and where (e2e, testnets, both) to do it
- Implementation of infra to test upgrades
DoD:
We are able to easily test upgrading Tendermint between two consecutive minor, or major versions
Related issue: tendermint/tendermint#8653