Use Java 24 instead of Java 23 in the CI Github action

To fix the broken build, and to focus on testing the Java
LTS versions and the latest one.

Author: sdeleuze

.github/workflows/ci.yml

@@ -20,7 +20,7 @@ jobs:
             toolchain: false
           - version: 21
             toolchain: true
-          - version: 23
+          - version: 24
             toolchain: true
         exclude:
           - os: