Remove optional gen parameter from bytes_size and string_size generators
#647
| Job | Run time |
|---|---|
| 4m 36s | |
| 6m 39s | |
| 3m 38s | |
| 3m 51s | |
| 4m 11s | |
| 5m 56s | |
| 3m 9s | |
| 4m 23s | |
| 2m 11s | |
| 4m 7s | |
| 1m 58s | |
| 2m 2s | |
| 1m 57s | |
| 6m 39s | |
| 2m 5s | |
| 6m 44s | |
| 2m 2s | |
| 4m 31s | |
| 6m 22s | |
| 2m 11s | |
| 6m 13s | |
| 2m 5s | |
| 7m 36s | |
| 1h 35m 6s |