8293768: Add links to JLS 19 and 20 from SourceVersion enum constants

Reviewed-by: iris, jjg

Author: jddarcy

src/java.compiler/share/classes/javax/lang/model/SourceVersion.java

@@ -351,6 +351,10 @@ public enum SourceVersion {
      * No major changes from the prior release.
      *
      * @since 19
+     *
+     * @see <a
+     * href="https://docs.oracle.com/javase/specs/jls/se19/html/index.html">
+     * <cite>The Java Language Specification, Java SE 19 Edition</cite></a>
      */
     RELEASE_19,
 
@@ -359,6 +363,10 @@ public enum SourceVersion {
      * 20.
      *
      * @since 20
+     *
+     * @see <a
+     * href="https://docs.oracle.com/javase/specs/jls/se20/html/index.html">
+     * <cite>The Java Language Specification, Java SE 20 Edition</cite></a>
      */
     RELEASE_20;