Disable vote buttons for bot accounts when on >=0.19.0

[Sjmarf]

As of 0.19.0 Lemmy will prevent bot accounts from voting. If the user is logged into a bot account, we should disable the vote options. https://github.com/LemmyNet/lemmy/pull/4100

[EricBAndrews]

Putting this in backlog because it's pretty low-priority--users aren't supposed to be using bot accounts anyway and the portion of affected users is certainly quite slim, so it's not a great value-for-dev-time proposition at this moment