include missing |None in concat and read_table stubs
#3373
| Job | Run time |
|---|---|
| 17s | |
| 7m 37s | |
| 4m 47s | |
| 4m 18s | |
| 2m 38s | |
| 4m 15s | |
| 4m 31s | |
| 5m 42s | |
| 2m 23s | |
| 5m 44s | |
| 5m 48s | |
| 4m 27s | |
| 2m 33s | |
| 55m 0s |