add sales point / exhibition place to retailers (#7)

src/collections/Retailers.ts

@@ -24,6 +24,11 @@ const Retailers: CollectionConfig = {
         type: 'relationship', // required
         relationTo: 'products', // required
         hasMany: true,
+      },
+      {
+        name: 'salesPoint',
+        type: 'text',
+        label: 'Where do you plan to sell/exhibit products?'
       }
   ],
 };