[c++] Fix dump_model() information for root node
#8842
| Job | Run time |
|---|---|
| 3s | |
| 8m 15s | |
| 8m 17s | |
| 8m 36s | |
| 1s | |
| 25m 12s |
dump_model() information for root node
#8842
| Job | Run time |
|---|---|
| 3s | |
| 8m 15s | |
| 8m 17s | |
| 8m 36s | |
| 1s | |
| 25m 12s |