Tweak builds on travis CI and ignore JDK 18 build for now
Tweak builds on travis CI and ignore JDK 18 build for now

apache/incubator-groovy,apache/incubator-groovy,paulk-asert/groovy,paulk-asert/groovy,paulk-asert/groovy,apache/groovy,paulk-asert/groovy,apache/incubator-groovy,apache/groovy,apache/groovy,apache/incubator-groovy,apache/groovy