fix test

Author: giancarloromeo

services/resource-usage-tracker/tests/unit/with_dbs/test_api_resource_tracker_credit_transactions.py

@@ -73,7 +73,7 @@ async def test_credit_transactions_workflow(
     )
     assert response.status_code == status.HTTP_201_CREATED
     data = response.json()
-    data["credit_transaction_id"] == 2
+    assert data["credit_transaction_id"] == 2
 
     response = await async_client.post(
         url=f"{url}",
@@ -99,4 +99,4 @@ async def test_credit_transactions_workflow(
     assert response.status_code == status.HTTP_200_OK
     data = response.json()
     assert data["wallet_id"] == 1
-    assert data["available_osparc_credits"] == Decimal(1340.04)
+    assert data["available_osparc_credits"] == "1340.04"