update CI config for for latest guava

Author: stoty

.github/workflows/main.yml

@@ -142,7 +142,7 @@ jobs:
     name: 'Linux (JDK 11), Newest Guava'
     runs-on: ubuntu-latest
     env:
-      GUAVA: 32.1.1-jre # newest supported Guava version
+      GUAVA: 33.4.0-jre # newest supported Guava version
     steps:
       - name: 'Set up JDK 11'
         uses: actions/setup-java@v4