Synthesis of (±)‐cis‐1‐Aryl‐3‐oxo‐2,3‐dihydro‐1H‐benzo[f]chromene‐2‐carbonitriles and (±)‐trans‐4‐Aryl‐2‐oxo‐3,4‐dihydro‐2H‐benzo[h]chromene‐3‐carbonitriles