Java API Link Detection / Generation

[rnc]

Under JDK11, it does not correctly handle
<detectJavaApiLink>true</detectJavaApiLink>
and generates invalid links e.g.
https://docs.oracle.com/en/java/javase/11/docs/api/java/lang/Throwable.html
instead of
https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/Throwable.html

Its possible to reproduce by changing

diff --git a/testing/pom.xml b/testing/pom.xml
index f8e2f7a..7da4386 100644
--- a/testing/pom.xml
+++ b/testing/pom.xml
@@ -75,10 +75,11 @@
 -header Header -bottom Bottom -group Extra org.apidesign.javadoc.testing:org.apidesign.javadoc ${testing.doclint}
                     </additionalOptions>
                     <failOnWarnings>true</failOnWarnings>
+                    <detectJavaApiLink>true</detectJavaApiLink>
                     <links>
                         <!-- JDK 10 and above uses element-list link -->
                         <!-- https://docs.oracle.com/javase/10/docs/api/element-list is a downloadable file -->
-                        <link>https://docs.oracle.com/javase/10/docs/api/</link>
+                        <!-- <link>https://docs.oracle.com/en/java/javase/11/docs/api/</link> -->
 
                         <!-- Reactor uses the older filename package-list -->
                         <!-- https://projectreactor.io/docs/core/release/api/package-list is a downloadable file -->

And using either an explicit link or detectJavaApiLink