Update app.py

app.py

@@ -225,7 +225,7 @@ if st.session_state.screen == 2:
                 st.rerun()
         with row4a_col2:
             if st.button("Next"):
-                if st.session_state.image_counter < len(st.session_state.results - 1:
+                if st.session_state.image_counter < len(st.session_state.results) - 1:
                     st.session_state.image_counter += 1
 
         # predictions