adopt key convention

Author: i-jey

ulc_mm_package/QtGUI/study_metadata_form.py

@@ -179,7 +179,7 @@ def check_required(self):
             self.btn_start.setEnabled(False)
 
     def get_form_input(self):
-        result = {"study_id": self.config_data["study_description"]["id"]}
+        result = {"study_id": self.config_data["study_description"]["key"]}
         errors = []
         for name, (widget, field) in self._widgets.items():
             t = field["datatype"]