feat(medusa, medusa-js, medusa-react): Implement Sales Channel list (#1815)

**What**
Support sales channel list in medusa, medusa-js and medusa-react

**How**

By implementing a new endpoint and the associated service method as well as the repository methods.

Medusa-js new list method in the resource

Medusa-react new hook in the queries

**Tests**

Endpoint test
Service test
Integration test
Hook tests

Fixes CORE-280

packages/medusa-react/src/hooks/admin/sales-channels/queries.ts

@@ -1,4 +1,8 @@
-import { AdminSalesChannelsRes } from "@medusajs/medusa"
+import {
+  AdminSalesChannelsRes,
+  AdminSalesChannelsListRes,
+  AdminGetSalesChannelsParams,
+} from "@medusajs/medusa"
 import { Response } from "@medusajs/medusa-js"
 import { useQuery } from "react-query"
 import { useMedusa } from "../../../contexts"
@@ -36,21 +40,26 @@ export const useAdminSalesChannel = (
   return { ...data, ...rest } as const
 }
 
-/*
+/**
+ * retrieve a list of sales channels
+ * @experimental This feature is under development and may change in the future.
+ * To use this feature please enable feature flag `sales_channels` in your medusa backend project.
+ * @description Retrieve a list of sales channel
+ * @returns a list of sales channel as well as the pagination properties
+ */
 export const useAdminSalesChannels = (
   query?: AdminGetSalesChannelsParams,
   options?: UseQueryOptionsWrapper<
-    Response<AdminProductsListRes>,
+    Response<AdminSalesChannelsListRes>,
     Error,
     ReturnType<SalesChannelsQueryKeys["list"]>
   >
 ) => {
   const { client } = useMedusa()
   const { data, ...rest } = useQuery(
-    adminProductKeys.list(query),
+    adminSalesChannelsKeys.list(query),
     () => client.admin.salesChannels.list(query),
     options
   )
   return { ...data, ...rest } as const
 }
-*/