This change adjusts the LDAP connection timeout for retrieving
attributes while performing the SAML IT to 5 seconds, from 5 ms
that it previously was.
Resolves: #40025
The change replaces the Vagrant box based fixture with a fixture
based on docker compose and 2 docker images, one for an openldap
server and one for a Shibboleth SAML Identity Provider.
The configuration of both openldap and shibboleth is identical to
the previous one, in order to minimize required changes in the
tests