update to compile with java 21

Author: skavanagh

.github/workflows/github-build-and-deploy.yml

@@ -18,7 +18,7 @@ jobs:
         uses: actions/setup-java@v5
         with:
           distribution: temurin
-          java-version: '17'
+          java-version: '21'
           cache: maven
           # This writes <server id="ossrh"> with id=ossrh
           server-id: ossrh

.github/workflows/github-build.yml

@@ -24,7 +24,7 @@ jobs:
         uses: actions/setup-java@v5
         with:
           distribution: temurin
-          java-version: '17'
+          java-version: '21'
           cache: maven
 
       # Import GPG only for trusted contexts (not forked PRs).
@@ -34,7 +34,7 @@ jobs:
         uses: actions/setup-java@v5
         with:
           distribution: temurin
-          java-version: '17'
+          java-version: '21'
           cache: maven
           gpg-private-key: ${{ secrets.OSSRH_GPG_SECRET_KEY }}
           gpg-passphrase:  ${{ secrets.OSSRH_GPG_SECRET_KEY_PASSWORD }}