Switch to the master constraint in tox.ini

To releas a new tag for Tempest 2024.2, we modified the
compatible constraint in tox.ini
- https://review.opendev.org/c/openstack/tempest/+/913950/

As new tag is released now so we can switch back to the master
constraint in tox.ini.

Change-Id: If8eef96fcdd5a6786e1326cafc6e75f61ced1348
2 files changed