Option to push timings instead of using the time it took to execute the function

[razzeee]

Hey there,

this seems like a great lib. I'm currently trying to figure out how to port https://github.com/elm-tooling/elm-language-server/blob/master/test/performance.ts which is basically running some times and each time getting six timing slices from the big function it's testing.

Is there any way I could push those times to this lib and end up with correct data? I'm especially interested in running it with https://github.com/rhysd/github-action-benchmark to make sure we're alerted if performance is hit in some way.

Thanks