include version 21 in tests

Author: aarsilv

.github/workflows/lint-test-sdk.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        java-version: ['8', '11', '17'] # Define the Java versions to test against
+        java-version: ['8', '11', '17', '21'] # Define the Java versions to test against
     steps:
       - uses: actions/checkout@v4
         with: