By Karolina Tagaris and Vassilis Triandafyllou NAXOS, Greece (Reuters) – In a small factory on the Greek island of Naxos, workers are busy churning out its famous graviera cheese. At least, they are for now. A crisis unfolding on the island’s farms is sparking fears that the locally-produced pale yellow wheels may soon start to disappear from the cheese counter. Standing among his cows in the scorching May sun, dairy farmer Stelios Zevlis says soaring prices of everything, driven by the war in Ukraine, have made feeding his animals unaffordable, forcing him to slaughter those too malnourished …