CI: build and test on JDK 24-ea

 - java hints job remains on 23 and has to wait for nb-javac 24

.github/workflows/main.yml

@@ -124,7 +124,7 @@ jobs:
     timeout-minutes: 40
     strategy:
       matrix:
-        java: [ '17', '21', '23' ]
+        java: [ '17', '21', '24-ea' ]
         exclude:
           - java: ${{ github.event_name == 'pull_request' && 'nothing' || '21' }}
       fail-fast: false
@@ -229,7 +229,7 @@ jobs:
         java: [ 17 ]
         include:
           - os: ubuntu-latest
-            java: 22
+            java: 24-ea
       fail-fast: false
     steps:
 
@@ -417,11 +417,11 @@ jobs:
         run: ant $OPTS build-nbms
 
       # 13-14 min for javadoc; JDK version must be synced with nb-javac
-      - name: Set up JDK 23 for javadoc
+      - name: Set up JDK 24-ea for javadoc
         if: env.test_javadoc == 'true' && success()
         uses: actions/setup-java@v4
         with:
-          java-version: 23 
+          java-version: 24-ea 
           distribution: ${{ env.DEFAULT_JAVA_DISTRIBUTION }}
 
       - name: Build javadoc
@@ -834,7 +834,7 @@ jobs:
     timeout-minutes: 50
     strategy:
       matrix:
-        java: [ '17', '21', '23' ]
+        java: [ '17', '21', '24-ea' ]
         exclude:
           - java: ${{ github.event_name == 'pull_request' && 'nothing' || '21' }}
       fail-fast: false
@@ -1494,7 +1494,7 @@ jobs:
     timeout-minutes: 60
     strategy:
       matrix:
-        java: [ '17', '21', '23' ]
+        java: [ '17', '21', '24-ea' ]
         exclude:
           - java: ${{ github.event_name == 'pull_request' && 'nothing' || '21' }}
       fail-fast: false