Bump Java to 11 in GHA test build

Author: acogoluegnes

.github/workflows/test-linux.yml

@@ -26,10 +26,11 @@ jobs:
     steps:
       - uses: actions/checkout@v2
 
-      - name: Set up JDK 1.8
-        uses: actions/setup-java@v1
+      - name: Set up JDK
+        uses: actions/setup-java@v2
         with:
-          java-version: 1.8
+          distribution: 'zulu'
+          java-version: '11'
       - name: Cache Maven packages
         uses: actions/cache@v2
         with: