update travis for 2.11
-language: java
# 08-Dec-2018, tatu: While it should be possible to run core streaming on Java 6,
# build won't work with anything below Java 8 now
+language: java
- openjdk8
- - oraclejdk11
+ - openjdk11
# Below this line is configuration for deploying to the Sonatype OSS repo
# https://knowm.org/configure-travis-ci-to-deploy-snapshots/
