fix various build issues

web/src/components/venues/VenueItem.tsx

@@ -9,9 +9,9 @@ export const VenueItem = ({ venue }: { venue: VenueFragment }) => {
   const { capacitySitting, capacityStanding, usedFor } = venue;
   let capacity = null;
   if (
-    !isNaN(capacitySitting) &&
+    !isNaN(Number(capacitySitting)) &&
     capacitySitting &&
-    !isNaN(capacityStanding) &&
+    !isNaN(Number(capacityStanding)) &&
     capacityStanding
   ) {
     capacity = `${capacitySitting}—${capacityStanding}`;