Backport PR pandas-dev#49437: CI: maybe fix docs build

Author: MarcoGorelli

doc/source/whatsnew/v0.13.0.rst

@@ -733,7 +733,7 @@ Enhancements
 
 .. _scipy: http://www.scipy.org
 .. _documentation: http://docs.scipy.org/doc/scipy/reference/interpolate.html#univariate-interpolation
-.. _guide: http://docs.scipy.org/doc/scipy/reference/tutorial/interpolate.html
+.. _guide: https://docs.scipy.org/doc/scipy/tutorial/interpolate.html
 
 - ``to_csv`` now takes a ``date_format`` keyword argument that specifies how
   output datetime objects should be formatted. Datetimes encountered in the