chore(ci): enable sccache for integration tests (#9597)
### Description
Enable sccache for building the turbo binary in integration tests.
### Testing Instructions
This should provide a speedup for our integration tests:
- [Normal
run](https://github.com/vercel/turborepo/actions/runs/12209798573?pr=9545):
- Ubuntu: 12m 17s
- macOs: 25m 45s
- Windows: 26m 13s
- [Run with
sccache](https://github.com/vercel/turborepo/actions/runs/12245380679?pr=9597)
- Ubuntu: 7m 8s
- macOs: 18m 44s
- Windows: 23m 31s
(I quick double checked that none of these were `turbo` cached, but they
did have a warmed `sccache` so external dep changes will degrade speed)
