Issue 49295 - Fix CI tests
Bug Description:
Previously test was changing system date back and forth in order to test
password expiration. This leads to breaking system under test in various ways,
especially when tests are running in parallel.
Fix Description:
Modify passwordExpirationTime attribute in the user entry instead.
https://pagure.io/389-ds-base/issue/49295
Reviewed by: mreynolds, wibrown (Thanks!)