Test and validate configurations of new Keycloak plugin env variables

Test and validate all working configurations of the following environment variables for the keycloak plugin:

KC_SPI_BABY_YODA_OCSP_ENABLED: "true"
KC_SPI_TRUSTSTORE_FILE_FILE: "/opt/keycloak/conf/truststore.jks"
KC_SPI_TRUSTSTORE_FILE_PASSWORD: "password"

See also: #138 (comment 2038936)