Fix portfolio dataframe handling in load_contest_file function

- Corrected the method used to filter portfolio_df by original_columns, changing from an incorrect operation to the appropriate column selection method.
- This change ensures that the portfolio dataframe is accurately structured, enhancing data integrity during contest file processing.

global_func/load_contest_file.py

@@ -167,7 +167,7 @@ def load_contest_file(upload, type, helper = None, sport = None, portfolio = Non
                 portfolio_df['BaseName'] = 'Backtesting_upload'
                 portfolio_df['EntryCount'] = len(portfolio_df)
                 original_columns = cleaned_df.columns.tolist()
-                portfolio_df = portfolio_df[original_columns]
+                portfolio_df = portfolio_df.columns(original_columns)
                 cleaned_df = pd.concat([cleaned_df, portfolio_df], ignore_index=True)
             
             # Get unique entry names