Hot spares will attempt to refresh votes which creates log spam

[AshwinSekar]

Problem

Previous efforts:
solana-labs#32315
solana-labs#34737

Non voting validators (--no-voting) have no authorized voter keypairs which is correctly signaled not to refresh.
However hotspares will have an invalid identity keypair, this is not handled - still leads to GenerateVoteTxResult::Failed which will be eligble for refresh.

Proposed Solution

Add another case for hotspares to avoid refresh.
Also since authorized voter keypair and identity can be adjusted on the fly, allow for refresh if those are changed.

Example

This is hotspare from Pumpkin (https://discord.com/channels/428295358100013066/560174212967432193/1278376793455202418):

[2024-08-28T15:39:49.682690040Z WARN  solana_core::consensus] Trying to refresh timestamp for vote on 289850363
                         using smaller heaviest bank 289850363
[2024-08-28T15:39:49.682717395Z INFO  solana_core::replay_stage] Vote account node_pubkey mismatch: Poo1fGex6LzoVSn1kkQcvTamyK8J4FvKnEUeZhkd9Bv (expected: 5JjSDGpppMmmVo97ZFnMkDgCFhyrH4aU7ZBHPDmzcZAK).  Unable to vote