Update dependency quay.io/keycloak/keycloak to v19.0.3

This MR contains the following updates:

Package	Type	Update	Change
quay.io/keycloak/keycloak	ironbank-docker	patch	19.0.2-legacy -> 19.0.3-legacy
quay.io/keycloak/keycloak		patch	19.0.2-legacy -> 19.0.3-legacy
quay.io/keycloak/keycloak	stage	patch	19.0.2-legacy -> 19.0.3-legacy

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