swift-server
Update Benchmark set up and persist benchmarks
We have recently updated our toolchain version to 5.9, but have never updated the benchmark suite to use 5.9 or newer. Also, it does not look like we ever commited a baseline to this repository.
While at it, wiring up GitHub actions to run the benchmarks for every pull request, as well as on a merge into main. Re-uses a lot of the heavy lifting that was defined in apple/swift-nio already.
Note that nightly-main appears broken at the moment. The Benchmark tool gets stuck, and initial debugging point to it never finishing _sendAndAcknowledgeMessages when producing a set of messages before every benchmark.
Right. So the benchmark performs worse on GitHub Actions than on my local machine. What's the blessed approach of introducing a baseline then?
