Update jboss/keycloak Docker tag to v13

This MR contains the following updates:

Package	Type	Update	Change
jboss/keycloak	ironbank-docker	major	12.0.4 -> 13.0.0
jboss/keycloak		major	12.0.4 -> 13.0.0
jboss/keycloak	stage	major	12.0.4 -> 13.0.0

---

Renovate configuration

📅 Schedule: At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻️ Rebasing: Whenever MR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this MR and you won't be reminded about these updates again.

---

• If you want to rebase/retry this MR, check this box

---

This MR has been generated by Renovate Bot.