use java 21 for android builds

Author: Totto16

.github/workflows/android.yml

@@ -39,7 +39,7 @@ jobs:
         uses: actions/setup-java@v4
         with:
           distribution: 'temurin'
-          java-version: '17'
+          java-version: '21'
 
       - name: Setup Android SDK
         uses: android-actions/setup-android@v3