support rb_binary with Gemfiles in subdirectory
#112
| Job | Run time |
|---|---|
| 28s | |
| 6m 39s | |
| 9m 10s | |
| 2m 12s | |
| 4m 59s | |
| 13m 23s | |
| 2m 33s | |
| 5m 25s | |
| 14m 0s | |
| 2m 18s | |
| 3m 23s | |
| 2m 47s | |
| 4m 15s | |
| 1m 49s | |
| 4m 57s | |
| 1h 18m 18s |