Change BasicCommandWithRequestParser::runWithRequestParser to take in DatabaseName, and then ChangeBasicCommandWithRequestParser::runWithReplyBuilder can pass the DatabaseName object to it directly.

Also, change BasicCommandWithRequestParser::_parseRequest to take in a DatabaseName object. If we've already done the work to pass a tenantId to the BSONObj parse function, pass the tenantId on the DatabaseName object to RequestType::parse() - otherwise can do this in a future ticket.

There are ~8 commands that override BasicCommandWithRequestParser::runWithRequestParser, we'll need to change these to use DatabaseName.