[nova][tc] Removing md5 in password injection

Hi, I didn't feel it would be controversial, though it seems removing md5 password injection is still up to debate: https://review.opendev.org/c/openstack/nova/+/935512 Of course, I'd like the TC to agree with me that injecting md5-hashed passwords is, in 2024, to be considered a security problem that should be fixed (and backported) ASAP. BTW, IMO this patch could be using the new feature from oslo_utils.secretutils that Takashi managed to get in: https://review.opendev.org/c/openstack/oslo.utils/+/931899 https://review.opendev.org/c/openstack/oslo.utils/+/935525 These, IMO, should also be backported to earlier oslo.utils releases, so we can fix earlier OpenStack releases in a nicer way. Cheers, Thomas Goirand (zigo)