making sure a broken run doesn't nuke the front end

src/streamlit_app.py

@@ -112,7 +112,7 @@ if selected_tab == "NHL Updates":
         roo_file, own_dicts = build_dk_player_level_basic_outcomes(slate_info, dk_player_hold, fd_player_hold, nhl_db)
 
         try:
-            if roo_file is not None:
+            if roo_file is not None and len(roo_file) > 0:
                 st.write("NHL Draftkings Player Level ROO refreshed")
                 st.table(roo_file.head(10))
             else: