fix(excel): remove unwanted index column from Excel exports (apache#38176)

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: rusackas

superset/common/query_context_processor.py

@@ -259,7 +259,9 @@ def get_data(
                 )
             elif self._query_context.result_format == ChartDataResultFormat.XLSX:
                 excel.apply_column_types(df, coltypes)
-                result = excel.df_to_excel(df, **current_app.config["EXCEL_EXPORT"])
+                result = excel.df_to_excel(
+                    df, index=include_index, **current_app.config["EXCEL_EXPORT"]
+                )
             return result or ""
 
         return df.to_dict(orient="records")

tests/unit_tests/common/test_query_context_processor.py

@@ -126,7 +126,7 @@ def test_get_data_xlsx(
     result = processor.get_data(df, coltypes)
     assert result == b"binary data"
     mock_apply_column_types.assert_called_once_with(df, coltypes)
-    mock_df_to_excel.assert_called_once_with(df)
+    mock_df_to_excel.assert_called_once_with(df, index=False)
 
 
 def test_get_data_json(processor, mock_query_context):
@@ -201,7 +201,7 @@ def test_get_data_empty_dataframe_xlsx(
     result = processor.get_data(df, coltypes)
     assert result == b"binary data empty"
     mock_apply_column_types.assert_called_once_with(df, coltypes)
-    mock_df_to_excel.assert_called_once_with(df)
+    mock_df_to_excel.assert_called_once_with(df, index=False)
 
 
 def test_get_data_nan_values_json(processor, mock_query_context):