Install Maven in Loom container to fix CI failure

Co-authored-by: franz1981 <13125299+franz1981@users.noreply.github.com>

Author: Copilot

.github/workflows/loom-tests.yml

@@ -21,6 +21,11 @@ jobs:
     steps:
     - uses: actions/checkout@v6
 
+    - name: Install Maven
+      run: |
+        apt-get update
+        apt-get install -y maven
+    
     - name: Verify Java version
       run: |
         java -version