Bumped up to JDK 11.

Author: cheeseng

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
       uses: actions/setup-java@v3
       with:
         distribution: temurin
-        java-version: 8
+        java-version: 11
     - name: Build and Test
       run: | 
         export DISPLAY=:99