Remove restriction on python version for ep-bolfi

[SarahRo]

GPy (https://github.com/SheffieldML/GPy) currently does not work with python 3.13

GPy is required for ep-bolfi.

GPy requires numpy<2.0.0 and scipy<=1.12.0

• Support for python 3.13 was added in SciPy 1.14.1 (https://docs.scipy.org/doc/scipy/release/1.14.1-notes.html). pip install fails for SciPy 1.12.0 with python 3.13
• Python 3.13 support for numpy added with version 2.1.0 (https://numpy.org/devdocs/release/2.1.0-notes.html). Although it would appear that nothing breaks with Python 3.13 and numpy 1.26.4

See #868

Related GPy Issues:
SheffieldML/GPy#1112
SheffieldML/GPy#1119