fix: Medusa service base method transaction (#7758)

**What**
Remove transaction decorator from the base medusa service method, the transaction will always be coming from the shared context. It fixes the issue that when you consume a base method directly it will return a proper tuple from the DB instead of the one from the entity map cc @VariableVic 

**NOTE**
This pr also fix some categories issues in the product module which was preventing the tests from working. if @sradevski you could have a look later, in the mean time we can still merge it

FIXES CORE-2342

packages/modules/workflow-engine-redis/integration-tests/__tests__/index.spec.ts

@@ -12,7 +12,7 @@ import "../__fixtures__"
 import { createScheduled } from "../__fixtures__/workflow_scheduled"
 import { DB_URL, TestDatabase } from "../utils"
 
-jest.setTimeout(50000)
+jest.setTimeout(100000)
 
 const sharedPgConnection = knex<any, any>({
   client: "pg",