Tooz 6.0.1 includes commit [1], which introduced
parsing the username from the Redis connection URL.
As a result, services started authenticating as admin
which, by the way, was incorrect even before, as either
a created user or the default one should have been used.
The reason it worked before is simply because the username
'admin' wasn't parsed anywhere.
This patch fixes the user being used and sets the correct
'default' one.
[1] https://review.opendev.org/c/openstack/tooz/+/907656
Closes-Bug: #2056667
Depends-On: https://review.opendev.org/c/openstack/kolla/+/911703
Change-Id: I5568dba15fa98e009ad4a9e41756aba0fa659371
59da07920b