Only 'A1' is cleared when clearing a sheet with frozen columns

[karelserruys-foodpairing]

Description

When trying to clear a sheet that has frozen columns and rows, only cell A1 is cleared. I think it's caused by this line of code: https://github.com/aiguofer/gspread-pandas/blob/60e8d93cab67290ccdf341ada12800a36e40ca01/gspread_pandas/spread.py#L606

Proposed solution

Revert this change: https://github.com/aiguofer/gspread-pandas/commit/60e8d93cab67290ccdf341ada12800a36e40ca01