CI: Use CrateDB nightly for PRs on Linux, lock version only on macOS
#848
| Job | Run time |
|---|---|
| 2m 1s | |
| 2m 4s | |
| 2m 7s | |
| 2m 3s | |
| 2m 2s | |
| 2m 3s | |
| 2m 19s | |
| 4m 14s | |
| 3m 36s | |
| 3m 25s | |
| 25m 54s |