Wrong documentation for enable_contract_version

[davidatwhiletrue]

This looks like a copy/paste issue:

Enable a version of a contract from the contract stored at the given hash. That version of the contract will no longer be callable by call_versioned_contract. Note that this contract must...

https://github.com/casper-network/casper-node/blob/5b95c0dae66e5dc02e4472f1a3089606d20d2afa/smart_contracts/contract/src/contract_api/storage.rs#L348

FIX by removing the line in bold: "That version of the contract will no longer be callable by call_versioned_contract."