TST: fix cupy to_device test on multiple devices
#1021
| Job | Run time |
|---|---|
| 8m 40s | |
| 13m 34s | |
| 22m 14s |
to_device test on multiple devices
#1021
| Job | Run time |
|---|---|
| 8m 40s | |
| 13m 34s | |
| 22m 14s |