[CMake] add hpp-pinocchio dependency to example test

required since https://github.com/humanoid-path-planner/hpp-pinocchio/pull/86

tests/plugin-test/CMakeLists.txt

@@ -20,4 +20,6 @@ SET_TARGET_PROPERTIES(example PROPERTIES PREFIX ""
   )
 
 TARGET_LINK_LIBRARIES(example ${LIBRARY_NAME})
+PKG_CONFIG_USE_DEPENDENCY(example hpp-pinocchio)
+
 #INSTALL(TARGETS example DESTINATION lib/hppPlugins)