Motivation
At the moment, the test_several_tools_add_and_remove benchmark is quite slow, since it subprocesses uv. There are pros and cons to that. But it would be very helpful to have a directly comparable benchmark which mocks uv giving a nice comparison between the two.

This is related to #241.

Summary of desired enhancement
Create an equivalent benchmark to test_several_tools_add_and_remove which mocks uv