Bump hacking

hacking 3.0.x is too old. Bump it to the version currently used in
tempest repo.

Also remove the note about old pip's behavior because recent pip does
not require specific order.

Depends-on: https://review.opendev.org/c/openstack/tempest/+/906634
Change-Id: I9a7760dcbcba15213deaa03e3c2a5f42446905d1
4 files changed