Fix opam init -yn asking questions on Windows
#3019
| Job | Run time |
|---|---|
| 6s | |
| 4s | |
| 44s | |
| 2m 23s | |
| 2m 25s | |
| 35m 24s | |
| 2m 4s | |
| 2m 12s | |
| 2m 10s | |
| 2m 16s | |
| 2m 6s | |
| 2m 14s | |
| 2m 0s | |
| 2m 2s | |
| 39m 22s | |
| 49m 27s | |
| 48m 40s | |
| 50m 26s | |
| 52m 36s | |
| 1m 47s | |
| 2m 11s | |
| 1m 13s | |
| 14m 36s | |
| 59s | |
| 5m 41s | |
| 59s | |
| 1m 30s | |
| 5h 27m 37s |