Callum McGregor is stepping back from his international career with Scotland to focus on performing for Celtic. McGregor has been a mainstay in the Scotland midfield for years, racking up 63 caps and representing his country at two major tournaments. Now, he’s explained the time is right for him to hang up his boots on the international scene in what should be seen as a boost for the Bhoys. McGregor will get critical periods of rest throughout the season, helping him recover mentally and physically. Celtic can only really benefit from that, as much as the player will miss performing for Scotla…