refactor: removed simapp imports

[poorphd]

Description

Currently, Canto does not use VoteExtension, so the corresponding baseapp option that uses the VoteExtensionHandler from simapp has been removed.
Moreover, the current VoteExtensionHandler from simapp is a dummy handler and should not be used in production.
https://github.com/cosmos/cosmos-sdk/blob/v0.50.7/simapp/abci.go#L15-L28

Closes: L-9

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[dudong2]

Is it ok to run a node without registering a vote extension handler?

[poorphd]

Yes, it's ok.
baseapp's ExtendVote and VerifyVoteExtension just return an error if handlers are not set (= vote extensions are not enabled).
https://github.com/cosmos/cosmos-sdk/blob/v0.50.7/baseapp/abci.go#L567-L572
https://github.com/cosmos/cosmos-sdk/blob/v0.50.7/baseapp/abci.go#L622-L627

[zsystm]

LGTM

note for vote extension option: when we run node without vote extension handler, we should make sure that vote extension is disabeld in cometBFT configuration.

• check VoteExtensionsEnableHeight is set to 0 in ConsensusParams (code ref: https://github.com/cometbft/cometbft/blob/8cd4a692d0fbd70f183e28f4507641c799a8f14f/consensus/state.go#L2383-L2394)