Use it to consistently place all temporary files created by tests in a overridable folder specific to the user, that is easy to cleanup later.
NOTE: os.temp_dir() on macos returns `/tmp`, and using `/tmp/v` is a problem when multiple unix users are trying to access/create/write to it.
vlib is the term for all modules included by default with V and
maintained as part of the V source code repository.
Some included modules depend on third party libraries, and these are kept
separate in the thirdparty directory at the root level of the source
repository.