CLN: GH19404 Changing function signature to match logic (#19425)

Author: Upkar Lidder

pandas/core/generic.py

@@ -1906,7 +1906,7 @@ def to_pickle(self, path, compression='infer',
         return to_pickle(self, path, compression=compression,
                          protocol=protocol)
 
-    def to_clipboard(self, excel=None, sep=None, **kwargs):
+    def to_clipboard(self, excel=True, sep=None, **kwargs):
         """
         Attempt to write text representation of object to the system clipboard
         This can be pasted into Excel, for example.

pandas/io/clipboards.py

@@ -63,7 +63,7 @@ def read_clipboard(sep=r'\s+', **kwargs):  # pragma: no cover
     return read_table(StringIO(text), sep=sep, **kwargs)
 
 
-def to_clipboard(obj, excel=None, sep=None, **kwargs):  # pragma: no cover
+def to_clipboard(obj, excel=True, sep=None, **kwargs):  # pragma: no cover
     """
     Attempt to write text representation of object to the system clipboard
     The clipboard can be then pasted into Excel for example.