chore: Modernize micro benchmarks

[bwplotka]

There's a small cleanup task for those interested to help.

We need to switch to b.Loop and ensure all b.Run cases follow key=value format as per #2107 (comment)

[sandaruwijewardhana]

/assign
I would like to do this

[radianceded]

Happy to pick this up. Plan: migrate the micro benchmarks that still loop on b.N to b.Loop, and normalize the b.Run case names to key=value format as discussed in #2107 (review comment r3965677376). Will run the affected benchmarks and go vet before opening the PR.

[radianceded]

Happy to pick this up. Plan: migrate the micro benchmarks that still loop on b.N to b.Loop, and normalize the b.Run case names to key=value format as discussed in #2107 (review comment r3965677376). Will run the affected benchmarks and go vet before opening the PR.