Update mtdna_backend.py

mtdna_backend.py

@@ -310,7 +310,7 @@ async def summarize_results(accession, stop_flag=None, niche_cases=None):
         rules = confidence_score.set_rules()
         print("start to compute confidence score")
         score, tier, explanations_score = confidence_score.compute_confidence_score_and_tier(signals_confidence_score,rules)
-        confidence_values = f"{tier} ({score})" + "\n" + explanations_score
+        confidence_values = f"{tier} ({score})" + "\n" + "\n".join(explanations_score)
         print("confidence_values: ", confidence_values)  
         if niche_cases:
             row = {