`PrepareProposal`/`ProcessProposal`: Compare `types.proto` in `feature/abci++ppp` and `v0.36.x`

[sub-issue of #9053]

Current discrepancies (as of 2022-08-11):
* `PrepareProposal`/`ProcessProposal` related:
* [ ] ConsensusParams
* [ ] BlockParams
* [ ] ABCI version field

Other unrelated discrepancies - to decide if we want them on v0.37.x
* Fields of `EventAttribute` from bytes to string
* Simplification of `ResponseCheckTx`
