Fix serialization in benchmark
```
INFO:     127.0.0.1:38826 - "GET /info?dataset=oelkrise%2FCRT HTTP/1.1" 404 Not Found
```
Fix serialization in benchmark: ```
INFO:     127.0.0.1:38826 - "GET /info?dataset=oelkrise%2FCRT HTTP/1.1" 404 Not Found
```