Diego Herrera Carcedo/Getty ImagesKUPYANSK, Ukraine—Ukrainian troops in Kupyansk are running low on ammunition and weapons as they fight to remain in control of a city that doesn’t even want to be saved from the Russians. In this eastern town, soldiers say that they are afraid that pro-Russian civilian collaborators might help to poison, bomb, or otherwise kill them because they believe that life under Vladimir Putin’s occupation would be better than living in a free Ukraine.Located in the easte