ESDF example needing pytest and matplotlib

[maxspahn]

As mentioned in #96, the example point_robot_esdf.py requires some packages that are not installed by default.

When I run point_robot_esdf directly, I receive the following errors. This didn't happen before and I suspect it's due to def test_edf_evaluation(proj_rgb):. Initially, I installed pytest and attempted to run it, but this only led to more error messages. Commenting out the code seems to solve the problem temporarily.
File "", line 1007, in _find_and_load
File "", line 984, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'pytest'

Suggested fix, remove all these parts that are not needed and if needed add comment.