Isolation and Characterization of Humulene‐Glucoside, Quercetagetin‐3,7‐Dimethyl Ether, Kaempferol‐6‐Hydroxy‐3,7‐Dimethyl Ether, and Quercetin‐3‐O‐Glucoside from Pulicaria laciniata with In Vitro and In Silico Assessment of Their Antioxidant, Antidiabetic, and Anti‐Alzheimer Activities | Synapse