sig#779 - Upgrade to Keycloak version 25

[evegufy]

Description

Upgrade centralidp and sharedidp to Keycloak version 25.
The latest version at this point in time is 25.0.6 (corresponding to Bitnami chart version 23.0.0)

Important: the Postgres version of the dependency needs to remain 15 (as that's the aligned version in TRG 5.07) and the Bitnami chart has already moved on to Postgres version 16 in the subchart.

Acceptance Criteria

• App version has been upgraded to v25
• Postgres version of the dependency is still 15

Benefits

Keeping up to date with the latest Keycloak releases offers several benefits like security patches and bug fixes as well as new features, see release notes.