Update dependency quay.io/keycloak/keycloak to v19

This MR contains the following updates:

Package	Type	Update	Change
quay.io/keycloak/keycloak	ironbank-docker	major	18.0.2 -> 19.0.0
quay.io/keycloak/keycloak		major	18.0.2 -> 19.0.0
quay.io/keycloak/keycloak	stage	major	18.0.2 -> 19.0.0

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