PV_PLUGIN_PATH with a python plugin breaks pvpython with scripts

Setting PV_PLUGIN_PATH to a directory containing a python plugin breaks pvython behavior with scripts (and arguments in general).

Steps to reproduce:

script.py:

from paraview.simple import *
Sphere()
Show()
Render()

• ./bin/pvpython script.py : expected behavior, sphere is showing up and command returns
• PV_PLUGIN_PATH=/path/to/paraview/Examples/Plugin/PythonAlgorithm/ ./bin/pvpython script.py: interactive python interpreter, script is not executed, unexpected