fix: default index is int in select_box

app.py

@@ -22,7 +22,7 @@ with st.sidebar:
     information = st.radio(
     "What information inside the are you interested in?",
     ('Receipt Summary', 'Receipt Menu Details', 'Extract all!'))
-    receipt = st.selectbox('Pick one receipt', ['1', '2', '3', '4', '5', '6'], index='6')
+    receipt = st.selectbox('Pick one receipt', ['1', '2', '3', '4', '5', '6'], index=5)
 
 st.text(f'{information} mode is ON!\nTarget receipt: {receipt}\n(opening image @:./img/receipt-{receipt}.png)')