fmt.Printf or fmt.Sprintf already know how to convert a
byteslice into a string when building the output; we shouldn't
incur the unnecessary string(byteslice) conversion.
Using Bencher, we can see improvements such as
https://dashboard.github.orijtech.com/benchmark/3245b8e4bbbd44a597480319aaa4b9fe
which in independent experiments show:
* time/op (ns/op)
FormatIt-8 1.2µs ± 2% 1.1µs ± 10% -11.77% (p=0.000 n=10+9)
* speed (MB/s)
FormatIt-8 0.71GB/s ± 2% 0.80GB/s ± 9% +13.59% (p=0.000 n=10+9)
* allocs/op (B/op)
FormatIt-8 2.0kB ± 0% 1.1kB ± 0% -45.62% (p=0.000 n=10+10)
* allocs/op (count/op)
FormatIt-8 11 ± 0% 9.0 ± 0% -18.18% (p=0.000 n=10+10)
Fixes#10363
d0f64dff2c