Use python venvs

sim/tests/endToEndTests/CMakeLists.txt

@@ -89,7 +89,7 @@ foreach(i RANGE ${LEN_CONFIGS})
   add_custom_target(
     pyOpenPASS_${CURRENT_TESTCASE}
     COMMAND ${CMAKE_COMMAND} -E copy ${CURRENT_CONFIG} ${CMAKE_CURRENT_LIST_DIR}/pyOpenPASS/${CURRENT_TESTCASE}.json
-    COMMAND ${Python3_EXECUTABLE} ${PYOPENPASS_ARGS}
+    COMMAND python ${PYOPENPASS_ARGS}
     WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}/pyOpenPASS
     )