Merge branch 'dev_check_ilastik_workflow' into 'staging'

Report expected class of model, not actual class of shell

See merge request !32

model_server/extensions/ilastik/models.py

@@ -62,7 +62,7 @@ class IlastikModel(Model):
             assert True
         if not isinstance(shell.workflow, self.get_workflow()):
             raise ParameterExpectedError(
-                f'Ilastik project file {self.project_file} does not describe an instance of {shell.workflow.__class__}'
+                f'Ilastik project file {self.project_file} does not describe an instance of {self.__class__}'
             )
         self.shell = shell