Update release.yml

Author: Oliver Weiler

.github/workflows/release.yml

@@ -14,6 +14,7 @@ jobs:
       - name: Set up GraalVM and Native Image
         uses: graalvm/setup-graalvm@v1
         with:
+          version: 20.0.1
           java-version: 20
           distribution: graalvm-community
           github-token: ${{ secrets.GITHUB_TOKEN }}