Update GH CI workflow

Change-Id: I8c723eda458752b30d9c84e5e6f4d5929abcf891

Author: kupietz

.github/workflows/ci_test.yml

@@ -7,15 +7,15 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
-      - name: Set up JDK 17
-        uses: actions/setup-java@v3
+      - name: Set up JDK 21
+        uses: actions/setup-java@v5
         with:
-          distribution: 'zulu'
-          java-version: '17'
+          distribution: 'temurin'
+          java-version: '21'
 
       - name: Build and install
         env:
-          MAVEN_OPTS: -Xss8m -Xms512m -Xmx4g
+          MAVEN_OPTS: -Xss16m -Xms2048m -Xmx16g
         run: mvn install -Dgpg.skip=true -B -V