benchmark: add options to filter and compare benchmarks

[lukekarrys]

Built on top of #319.

This adds options to the benchmarks via util.parseArgs which allow for:

• filtering benchmark cases. This was helpful in benchmarking refactor: move to native fs.promises #314 because there was no reason to benchmark old or system rimraf. By default all benchmarks are included by individual ones can be picked with --cases or omitted with --omit-cases. For refactor: move to native fs.promises #314, I ran node benchmark/index.js -osystem -oold -oparallel which uses the short option -o to omit old, system, and parallel benchmarks.
• Saving and comparing benchmark runs. --save will save the benchmark results and options to a file benchmark-${Date.now()} and then --compare=benchmark-1728082932414.json can be used later. This will add old mean and % +/- columns to the table output comparing the current run with the file read from --compare.

[lukekarrys]

Closing in favor of #322