[dev-util/kdevelop-python] Remove unused dependency wrt bug #478504.

It was originally removed in 3e40b8f383a92e3e8055f45e66081357ce68264c,
and then accidentally readded in 8d8cf10b7894b39a00183797e62f2a0626c8458f.

Package-Manager: portage-2.2.8-r1