Duplicate codes

[benbaley]

System information

PlatON version: platon version
OS & Version: Windows/Linux/OSX
Commit hash : e11fe5c58e455c1cb637025d2fb167a54af4faf6

https://github.com/PlatONnetwork/PlatON-Go/blob/develop/x/gov/gov_db.go#L393

L395 duplicate with L407

func MovePreActiveProposalIDToEnd(blockHash common.Hash, proposalID common.Hash) error {
	//only one proposalID in PreActiveProposalIDList, so, just set it empty.
	err := del(blockHash, KeyPreActiveProposal())
	if err != nil {
		return err
	}

	// add this proposal ID to End list
	err = addProposalByKey(blockHash, KeyEndProposals(), proposalID)
	if err != nil {
		return err
	}

	// remove the pre-active version
	err = delPreActiveVersion(blockHash)
	if err != nil {
		return err
	}

	return nil
}

[benbaley]

The former is to delete Proposal, the latter is to delete version, non-issue