Fix booking API endpoint month format by changing separator from '/'to '-'. (#369)

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lib/utils/constants/api_const.dart

@@ -147,6 +147,6 @@ abstract class ApiEndpoints {
   static const String bookableSpaces = '/bookable-spaces';
   static const String getCalendarEvents = '/api';
   static const String getBookings =
-      '/bookings?month={mm}%2F{yyyy}&space={space}';
+      '/bookings?month={mm}-{yyyy}&space={space}';
 
 }