add benchmarks to CI

[Krastanov]

Currently we have a CI job that automatically tries to run benchmarks and detect regressions, but we have not actually added benchmarks scripts to the package.

To add them we can follow some of these examples:

https://github.com/JuliaDynamics/ResumableFunctions.jl/blob/master/benchmark/benchmarks.jl

https://github.com/QuantumSavory/QuantumSavory.jl/blob/master/benchmark/benchmarks.jl

https://github.com/QuantumSavory/QuantumClifford.jl/blob/master/benchmark/benchmarks.jl