Several times, have seen a random failure in testing - a nonsense SQL…

… complaint about a count() call (that works 99.9% of the time). Replace with SQLAlchemy `.first()` seems to fix.

portal/models/qb_status.py

@@ -49,8 +49,8 @@ def _sync_timeline(self):
 
         completed = QBT.query.filter(QBT.user_id == self.user.id).filter(
             QBT.research_study_id == self.research_study_id).filter(
-            QBT.status == OverallStatus.completed).count()
-        self.at_least_one_completed = completed > 0
+            QBT.status == OverallStatus.completed).with_entities(QBT.id).first()
+        self.at_least_one_completed = completed is not None
 
         # Obtain withdrawal date if applicable
         withdrawn = QBT.query.filter(QBT.user_id == self.user.id).filter(