Replace server's AdminTestCaseUtils by the SDK equivalent

Jean-Noël Rouvignac

21.24.2016 0c4fd5b96ee97c414f6a120e7bb683e94bdd1caf

opendj-server-legacy/src/test/java/org/forgerock/opendj/config/server/AdminTestCaseUtils.java does not exist in tree 3178e049cc0fb5c6089438c0e7661385ef3715f5