Fix the major version of Java 21.

66 is Java 22. 65 is Java 21.

Author: cescoffier

core/deployment/src/main/java/io/quarkus/deployment/pkg/builditem/CompiledJavaVersionBuildItem.java

@@ -76,7 +76,7 @@ final class Known implements JavaVersion {
             private static final int JAVA_11_MAJOR = 55;
             private static final int JAVA_17_MAJOR = 61;
             private static final int JAVA_19_MAJOR = 63;
-            private static final int JAVA_21_MAJOR = 66;
+            private static final int JAVA_21_MAJOR = 65;
 
             private final int determinedMajor;