update jdk

Author: Taz03

.github/workflows/docs.yml

@@ -14,10 +14,10 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Set up JDK 17
+      - name: Set up JDK
         uses: actions/setup-java@v4
         with:
-          java-version: '17'
+          java-version: '21'
           distribution: 'oracle'
 
       - name: Setup Gradle