Make experiment for calculating overhead in using multiprocessing

[valer1435]

Perform experiment:

1. Run fitting n pipelines in multiprocessing mode
2. Run fitting n pipelines in single process mode
3. Calculate overhead for creating a process

[gkirgizov]

I also have these thoughts:

• This experiment should be done as something reproducible (let's say, as a file in cases or examples) -- so we could run it on different systems if needed and later for new FEDOT versions. Thus we will be able to monitor performance improvements.
• Would be good to separate effects from multiprocessing from effects from cache. So trying to run same thing with & without OperationsCache seems a good idea.
• A good experimental question is: what's the minimum size of population to win the overhead and get real benefits?

All this would help to make performance improvements in FEDOT with much better understanding.

[valer1435]

Results of experiments can be obtained here https://arxiv.org/abs/2301.05102