Remove trailing whitespace

Author: tomas-cc

pandas/core/generic.py

@@ -2204,7 +2204,7 @@ def to_excel(
 
         Multiple sheets may be written to by specifying unique `sheet_name`.
         With all data written to the file it is necessary to save the changes.
-        Note that creating an `ExcelWriter` object with a file name that already exists 
+        Note that creating an `ExcelWriter` object with a file name that already exists
         will overwrite the existing file because the default mode is write.
 
         Parameters