minor cosmetic fix in the app.py file

app.py

@@ -88,7 +88,7 @@ def train_test_split_data(df):
 with header:
     st.title("Explaining Heart Diseases ML Model")
     st.markdown("""
-        Many people say machine learning models are **black boxes**, in the sense that they can make good predictions but you can't understand the logic behind those predictions. This statement is true in the sense that most data scientists don't know how to extract insights from models yet.")
+        Many people say machine learning models are **black boxes**, in the sense that they can make good predictions but you can't understand the logic behind those predictions. This statement is true in the sense that most data scientists don't know how to extract insights from models yet.
         
         This interactive application explains the presence of heart disease in a person based on [Heart Disease UCI](https://archive.ics.uci.edu/ml/datasets/Heart+Disease) dataset using **Explainable AI** technique.
     """)