New port category suggestions: machine-learning and quantum-computing

[Yuri]

Since there are more and more ports added for these two new areas are, I 
am suggesting to add these as new categories to the ports tree:

* https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=272625
* https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=272626



Thanks,

Yuri