remove java 8 from build and add java 17

Author: achimgrimm

.github/workflows/gradle.yml

@@ -16,10 +16,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-    - name: Set up JDK 1.8
+    - name: Set up JDK 11
       uses: actions/setup-java@v1
       with:
-        java-version: 1.8
+        java-version: 11
     - name: Grant execute permission for gradlew
       run: chmod +x gradlew
     - name: Build with Gradle

.travis.yml

@@ -1,8 +1,8 @@
 language: java
 jdk:
   - oraclejdk11
-  - openjdk8
   - openjdk11
+  - openjdk17
 before_cache:
   - rm --force             $HOME/.gradle/caches/modules-2/modules-2.lock
   - rm --force --recursive $HOME/.gradle/caches/*/plugin-resolution/