[FEATURE REQUEST] Run Vulture make_config() as to allow loading of pyproject.toml

[laundmo]

Is your feature request related to a problem? Please describe.
Vulture often false-positives when using Frameworks like Flask, since it doesn't know that decorated functions are called by the framework. This obviously leads to a lot of mistaken errors.

Describe the solution you'd like
I would like Prospector to run Vulture similar to how the main() function in Vulture runs, by first loading the config using vulture.config.make_config(). This would allow Vulture to load the pyproject.toml.

Describe alternatives you've considered
Alternatives could include Prospector handing the config for Vulture, but allowing config through the pyproject.toml would mean that config changes dont need to be added to Prospector.

Additional context
Possibly related to #376