push.yml: test with JDK v26 instead of v25

Author: stephengold

.github/workflows/push.yml

@@ -21,15 +21,15 @@ jobs:
           archive: false
           path: build/distributions/Maud.tar
 
-  Java25-Windows:
+  Java26-Windows:
     if: contains(toJson(github.event.commits), '[ci skip] ') == false
     runs-on: windows-2025
     steps:
       - uses: actions/checkout@v6
       - uses: actions/setup-java@v5
         with:
           distribution: 'liberica'
-          java-version: 25
+          java-version: 26
       - run: ./gradlew build javadoc --console=plain --stacktrace
         shell: bash
       - uses: actions/upload-artifact@v7