MM-15198 Migrate Channel.Get/GetFromMaster to Sync by default (#10667)

* MM-15198 Migrate Channel.Get/GetFromMaster to Sync by default

* MM-15198 - Update store/storetest/post_store.go

fix error handling in post_store.go test case

Co-Authored-By: andresoro <ao15@my.fsu.edu>

app/webhook.go

@@ -401,13 +401,9 @@ func (a *App) CreateOutgoingWebhook(hook *model.OutgoingWebhook) (*model.Outgoin
 	}
 
 	if len(hook.ChannelId) != 0 {
-		cchan := a.Srv.Store.Channel().Get(hook.ChannelId, true)
-
-		var channel *model.Channel
-		if result := <-cchan; result.Err != nil {
-			return nil, result.Err
-		} else {
-			channel = result.Data.(*model.Channel)
+		channel, errCh := a.Srv.Store.Channel().Get(hook.ChannelId, true)
+		if errCh != nil {
+			return nil, errCh
 		}
 
 		if channel.Type != model.CHANNEL_OPEN {
@@ -641,7 +637,11 @@ func (a *App) HandleIncomingWebhook(hookId string, req *model.IncomingWebhookReq
 			cchan = a.Srv.Store.Channel().GetByName(hook.TeamId, channelName, true)
 		}
 	} else {
-		cchan = a.Srv.Store.Channel().Get(hook.ChannelId, true)
+		var err *model.AppError
+		channel, err = a.Srv.Store.Channel().Get(hook.ChannelId, true)
+		if err != nil {
+			return model.NewAppError("HandleIncomingWebhook", "web.incoming_webhook.channel.app_error", nil, "err="+err.Message, err.StatusCode)
+		}
 	}
 
 	if channel == nil {