MM-15116 Migrate WebHook.SaveIncoming Method to Sync by default (#10663)

* SyncStore: migrate WebHooks.SaveIncoming method to Sync

* MM-15116 Migrates the WebHook.SaveIncoming method to Sync by default

* MM-15116 Migrate Webhook.SaveIncoming to Sync by default - fix minor typo

* MM-15116 Migrate WebHook.SaveIncoming to sync -  update test case

store/sqlstore/webhook_store.go

@@ -88,24 +88,23 @@ func (s SqlWebhookStore) InvalidateWebhookCache(webhookId string) {
 	}
 }
 
-func (s SqlWebhookStore) SaveIncoming(webhook *model.IncomingWebhook) store.StoreChannel {
-	return store.Do(func(result *store.StoreResult) {
-		if len(webhook.Id) > 0 {
-			result.Err = model.NewAppError("SqlWebhookStore.SaveIncoming", "store.sql_webhooks.save_incoming.existing.app_error", nil, "id="+webhook.Id, http.StatusBadRequest)
-			return
-		}
+func (s SqlWebhookStore) SaveIncoming(webhook *model.IncomingWebhook) (*model.IncomingWebhook, *model.AppError) {
 
-		webhook.PreSave()
-		if result.Err = webhook.IsValid(); result.Err != nil {
-			return
-		}
+	if len(webhook.Id) > 0 {
+		return nil, model.NewAppError("SqlWebhookStore.SaveIncoming", "store.sql_webhooks.save_incoming.existing.app_error", nil, "id="+webhook.Id, http.StatusBadRequest)
+	}
+
+	webhook.PreSave()
+	if err := webhook.IsValid(); err != nil {
+		return nil, err
+	}
+
+	if err := s.GetMaster().Insert(webhook); err != nil {
+		return nil, model.NewAppError("SqlWebhookStore.SaveIncoming", "store.sql_webhooks.save_incoming.app_error", nil, "id="+webhook.Id+", "+err.Error(), http.StatusInternalServerError)
+	}
+
+	return webhook, nil
 
-		if err := s.GetMaster().Insert(webhook); err != nil {
-			result.Err = model.NewAppError("SqlWebhookStore.SaveIncoming", "store.sql_webhooks.save_incoming.app_error", nil, "id="+webhook.Id+", "+err.Error(), http.StatusInternalServerError)
-		} else {
-			result.Data = webhook
-		}
-	})
 }
 
 func (s SqlWebhookStore) UpdateIncoming(hook *model.IncomingWebhook) (*model.IncomingWebhook, *model.AppError) {