OAK-1267: Failure in ObservationRefreshTest
OAK-1477: ObservationRefreshTest very slow for DOCUMENT_JDBC fixture
Don't run tests in parallel to avoid competing for resources
Exclude DOCUMENT_JDBC fixture

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1572492 13f79535-47bb-0310-9956-ffa450edef68