Use stable channel to build CedarJavaFFI in CI (#206)

Signed-off-by: Shaobo He <shaobohe@amazon.com>

Author: shaobo-he-aws

.github/workflows/build_java_hello_world_reusable.yml

@@ -16,7 +16,7 @@ jobs:
     strategy:
       matrix:
         toolchain:
-          - '1.80'
+          - stable
     steps:
       - name: Setup Java
         uses: actions/setup-java@v4