Use Java 24 in builds, only Java 11 for Windows and MacOS

.github/workflows/build.yml

@@ -61,9 +61,22 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os-name: [ubuntu-latest, macos-latest, windows-latest]
+        os-name: [ubuntu-latest]
         java-version: [11, 23]
         maven: [default, prerequisite]
+        include:
+          # Validate builds on Windows and MacOS.
+          - os-name: macos-latest
+            java-version: 11
+            maven: default
+          - os-name: windows-latest
+            java-version: 11
+            maven: default
+
+          # Validate against the next JDK preview.
+          - os-name: ubuntu-latest
+            java-version: 24-ea
+            maven: default
 
     steps:
       - name: Checkout code
@@ -82,7 +95,7 @@ jobs:
         run: |-
           version=$(./mvnw -B -T1 -q -pl protobuf-maven-plugin help:evaluate -DforceStdout -Dexpression='project.prerequisites.maven')
           ./mvnw -B -T1 -q wrapper:wrapper "-Dmaven=${version}"
-  
+
       - name: Install protoc to $PATH
         shell: bash
         run: scripts/install-protoc-to-github-runner.sh