Speed up CI

[k88hudson-cfa]

Right now our overall build times are very slow (~27 min total over the last 20 runs, see analysis below)

  │   Workflow    │  Avg  │ Median │  Min  │  Max  │
  ├───────────────┼───────┼────────┼───────┼───────┤
  │ check-test    │ 5.6m  │ 6.1m   │ 2.3m  │ 7.5m  │
  ├───────────────┼───────┼────────┼───────┼───────┤
  │ bench-compare │ 20.9m │ 20.6m  │ 18.6m │ 28.4m │

• improve caching for setup-env
• Split check-test into parallel jobs
• reduce redundant builds in benchmark baseline, maybe we could do dev with optimization on for setup-env and use that for everything?
• Parallel jobs for hyperfine and criterion
• Restrict benchmarks to a "run-benchmark" tag or if you change ixa-bench/** for PRs