[spec] Upgrade var-op-test from bash 4 to bash 5
#8830
| Job | Run time |
|---|---|
| 7m 34s | |
| 5m 11s | |
| 14s | |
| 3m 50s | |
| 2m 14s | |
| 23s | |
| 9m 28s | |
| 10m 11s | |
| 4m 35s | |
| 6m 23s | |
| 5m 20s | |
| 3m 13s | |
| 5m 32s | |
| 3m 33s | |
| 1m 8s | |
| 3m 25s | |
| 1m 11s | |
| 9s | |
| 1h 13m 34s |