rate limited http transport

[LukasJenicek]

[github-actions[bot]]

Benchmark Results

goos: linux
goarch: amd64
pkg: github.com/go-chi/httprate
cpu: AMD EPYC 7763 64-Core Processor                
               │ master.txt  │            pr.txt             │
               │   sec/op    │   sec/op     vs base          │
LocalCounter-4   19.90m ± 1%   19.92m ± 1%  ~ (p=0.853 n=10)

               │  master.txt  │             pr.txt             │
               │     B/op     │     B/op      vs base          │
LocalCounter-4   2.830Mi ± 0%   2.829Mi ± 0%  ~ (p=0.739 n=10)

               │ master.txt  │            pr.txt             │
               │  allocs/op  │  allocs/op   vs base          │
LocalCounter-4   121.4k ± 0%   121.4k ± 0%  ~ (p=0.753 n=10)