A growing scarcity of oil storage space is driving some of the world’s biggest crude producers to negotiate a truce this week in a Saudi-Russian fight for market share that has contributed—along with the coronavirus pandemic—to the recent oil-price rout. Ahead of a crucial summit set for Thursday, Saudi Arabia and others in OPEC are working to convince oil producers that there will be very little space left to store their oil if they don’t curb production, as oil traders scramble for empty vaults in remote corners of the oil…