Opted in validators do not get jailed twice

[p-offtermatt]

Problem

When they already were jailed, it seems opt-in validators sometimes do not get jailed again after they unjail and commit another downtime infraction.

Problem details

Steps to reproduce

1. Sync consumer node with a non-top N validator
2. Opt-in
3. Stop consumer node, get jailed
4. Sync consumer node again
5. Submit unjail tx in provider chain
6. Stop consumer node a second time- validator does not get jailed [Validator still shows up in tendermint-validator-set for both provider and top-N consumer]

[p-offtermatt]

This was not an issue, but just happened due to slash-throttling; #1752 adds a test for the scenario