add spirv-unknown-naga-wgsl target via naga
#490
| Job | Run time |
|---|---|
| 9m 59s | |
| 9m 45s | |
| 18m 43s | |
| 1m 10s | |
| 8m 8s | |
| 11m 26s | |
| 6m 22s | |
| 4m 34s | |
| 16m 50s | |
| 4m 50s | |
| 9m 29s | |
| 4m 46s | |
| 4m 33s | |
| 0s | |
| 1h 50m 35s |