In a sign that oil markets are returning to relative normality, the once yawning gap between the price of an actual physical barrel of oil and futures prices has narrowed sharply. At its worst in April, a barrel of oil in the North Sea cost $10 less than the price on a Brent oil futures contract, a decade-high gap for the world’s benchmark oil price, according to S&P Global Platts. Now, the gap has shrunk to less than $2 a barrel as the oil market rebalances and traders are no longer in panic mode to find buyers for unwanted…