[BUG]: call "Retrieve current usage" API，no return value

[ytrjp]

[BUG]: call "Retrieve current usage" API，no return value

[ytrjp]

restart lago-api docker server, Retrieve current usage API back to available

[ytrjp]

1. call current usage API
   {
   "customer_usage": {
   "from_datetime": "2024-04-26T02:25:28Z",
   "to_datetime": "2024-04-30T23:59:59Z",
   "issuing_date": "2024-04-30",
   "currency": "CNY",
   "amount_cents": 2000,
   "total_amount_cents": 2000,
   "taxes_amount_cents": 0,
   "lago_invoice_id": null,
   "from_date": "2024-04-26",
   "to_date": "2024-04-30",
   "amount_currency": "CNY",
   "total_amount_currency": "CNY",
   "vat_amount_currency": "CNY",
   "vat_amount_cents": 0,
   "charges_usage": [
   {
   "units": "0.0",
   "events_count": 0,
   "amount_cents": 0,
   "amount_currency": "CNY",
   "charge": {
   "lago_id": "55d41098-31c6-4c65-b1f9-bb325878b443",
   "charge_model": "package",
   "invoice_display_name": ""
   },
   "billable_metric": {
   "lago_id": "6e6b5d33-5951-4039-a957-0bf1ba31bffc",
   "name": "存储容量",
   "code": "storage",
   "aggregation_type": "sum_agg"
   },
   "filters": [],
   "groups": [],
   "grouped_usage": []
   },
   {
   "units": "2007442.0",
   "events_count": 11,
   "amount_cents": 2000,
   "amount_currency": "CNY",
   "charge": {
   "lago_id": "9799cc58-c174-4d3d-a263-a4c17afb86b2",
   "charge_model": "package",
   "invoice_display_name": ""
   },
   "billable_metric": {
   "lago_id": "9c0a2dbd-2a1c-41a7-9b37-e3643f31a74a",
   "name": "视频时长",
   "code": "gen_video_duration",
   "aggregation_type": "sum_agg"
   },
   "filters": [],
   "groups": [],
   "grouped_usage": []
   }
   ]
   }
   }

2. send event
   {
   "event": {
   "transaction_id": "ea81bb9b-dc32-4393-ab63-86a0c178a772_1557_1714295412",
   "external_customer_id": "ea81bb9b-dc32-4393-ab63-86a0c178a772",
   "external_subscription_id": "payment_20240426_022511_14eb776",
   "code": "gen_video_duration",
   "timestamp": 1714295412,
   "properties": {
   "plan_code": "month_vip",
   "storage_usage": 0,
   "gen_video_duration_usage": 100600
   }
   }
   }

3. call current usage API
   units：not change

"units": "2007442.0",
"events_count": 11,
"amount_cents": 2000,
"amount_currency": "CNY",
"charge": {
"lago_id": "9799cc58-c174-4d3d-a263-a4c17afb86b2",
"charge_model": "package",
"invoice_display_name": ""
},