[Java] Drop Oracle Java 8 from Travis tests.

Author: mjpt777

.travis.yml

@@ -3,12 +3,6 @@ sudo: false
 matrix:
   include:
 
-    - name: "Oracle Java 8"
-      language: java
-      jdk: oraclejdk8
-      os: linux
-      script: ./gradlew
-
     - name: "OpenJDK 8"
       language: java
       jdk: openjdk8