Update vthreads.yml

Author: fogus

.github/workflows/vthreads.yml

@@ -52,3 +52,11 @@ jobs:
       uses: actions/checkout@v4
       with:
           ref: ${{ github.event.inputs.asyncRef }}
+    - name: Set up Java
+      uses: actions/setup-java@v4
+      with:
+          java-version: ${{ matrix.java-version }}
+          distribution: 'temurin'
+          cache: 'maven'
+    - name: Compile tests
+      run: clj -T:build ${{ matrix.compile-mode }}