[ModelicaSystem] fix _getconn => _session

Author: syntron

OMPython/ModelicaSystem.py

@@ -1629,7 +1629,7 @@ def convertMo2Fmu(
         properties = (f'version="{version}", fmuType="{fmuType}", '
                       f'fileNamePrefix="{fileNamePrefix}", includeResources={includeResourcesStr}')
         fmu = self._requestApi(apiName='buildModelFMU', entity=self._model_name, properties=properties)
-        fmu_path = self._getconn.omcpath(fmu)
+        fmu_path = self._session.omcpath(fmu)
 
         # report proper error message
         if not fmu_path.is_file():
@@ -1650,7 +1650,7 @@ def convertFmu2Mo(
         >>> convertFmu2Mo("c:/BouncingBall.Fmu")
         """
 
-        fmu_path = self._getconn.omcpath(fmu)
+        fmu_path = self._session.omcpath(fmu)
 
         if not fmu_path.is_file():
             raise ModelicaSystemError(f"Missing FMU file: {fmu_path.as_posix()}")