608 Backend send confirmation on manual booking (#718)

* Change /bookings/create-booking to take a single userid

Changed tests and updated interfaces

* Move create-bookings from BookingController to AdminController

Moved corresponding tests too.

Next objective is to update frontend

* Change client to use /admin/bookings/create

Changed client end to use the endpoint specified instead of /bookings/create-bookings

* Edit AdminController to use an Array of dates & users

Revert change to `UIdssByDateRangeResponse` interface

* Add mail service for manual bookings

Also fixed some weird conflicts

* Add jest mock for nodemailer

This fixes the error while running `yarn test`

client/src/components/composite/Admin/AdminBookingView/WrappedAdminBookingCreationPopUp.tsx

@@ -43,7 +43,7 @@ const WrappedAdminBookingCreationPopUp = ({
         isPending={isPending}
         isLoading={hasNextPage}
         bookingCreationHandler={async (startDate, endDate, uid) => {
-          await handleAddUserToBooking({ startDate, endDate, userIds: [uid] })
+          await handleAddUserToBooking({ startDate, endDate, userId: uid })
         }}
       />
     </span>

client/src/services/Admin/AdminService.ts

@@ -143,26 +143,26 @@ const AdminService = {
   addUsersToBookingForDateRange: async function ({
     startDate,
     endDate,
-    userIds
+    userId
   }: {
     startDate: Timestamp
     endDate: Timestamp
-    userIds: string[]
+    userId: string
   }) {
     const { response, data } = await fetchClient.POST(
-      "/bookings/create-bookings",
+      "/admin/bookings/create",
       {
         body: {
           startDate,
           endDate,
-          userIds
+          userId
         }
       }
     )
 
     if (!response.ok) {
       throw new Error(
-        `Failed to add the users ${userIds.join(",")} to the date range ${startDate.toString()} to ${endDate.toString()} `
+        `Failed to add the user, ${userId} to the date range ${startDate.toString()} to ${endDate.toString()} `
       )
     }