fix: remove usage of set_obj_sense in test_update

Author: eminyouskn

tests/test_update.py

@@ -40,8 +40,8 @@ def test_update(model_interface):
 
     model.set_variable_attribute(x[0], poi.VariableAttribute.LowerBound, 1.5)
     model.set_variable_attribute(x[2], poi.VariableAttribute.LowerBound, 0.5)
-    model.set_objective_coefficient(x[0], -2.0)
-    model.set_obj_sense(poi.ObjectiveSense.Maximize)
+    model.set_objective_coefficient(x[0], 2.0)
+    model.set_objective_coefficient(x[2], 1.0)
     model.optimize()
 
     assert model.get_value(x[0]) == approx(1.5)