test(turbopack): Make HMR benchmark less flaky (#80488)
### What?
Retry HMR benchmarks, but make it less flaky.
This PR
- Removes flaky benchmarks (`hmr_initial_compilation`, `hmr_subscription`)
- Moves flaky parts (`benchmark_initial_compilation`) out of the iteration loop by moving them to the setup phase.
### Why?
We need a stable benchmark for dev performance.
