Feat(auth): Rename authentication to auth (#6229)

**What**
- rename `authenticationModule` -> `authModule`

packages/auth/integration-tests/utils/config.ts

@@ -0,0 +1,6 @@
+import { ModuleServiceInitializeOptions } from "@medusajs/types"
+
+export const databaseOptions: ModuleServiceInitializeOptions["database"] = {
+  schema: "public",
+  clientUrl: "medusa-auth-test",
+}