Improved Radiosynthesis and Automation of [11C]2‐(2,6‐Difluoro‐4‐((2‐(N‐methylphenylsulfonamido)ethyl)thio)phenoxy)acetamide ([11C]K2) for Positron Emission Tomography of the Glutamate α‐Amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole Propionic Acid (AMPA) Receptor