Using run_benchmark() for R benchmarks and the state of result schemas

[alistaire47]

I wrote a doc about what is required to run the R benchmarks via BenchmarkR with arrowbench::run_benchmark() (which runs for each case) instead of arrowbench::run_one() (which runs for a single case). A major part of this is making sure the right data and metadata from each run flows around correctly such that eventually it can be POSTed to conbench, so the doc devotes a lot of time to benchmark result (at the case level) schemas.

The implication is probably moving to a more standardized and unified form of benchmark result schema across the different levels and languages, so please add comments with opinions on what that might look like.