[Entitlements] Fix AbstractDelegateHttpsURLConnection "this" parameter type (elastic#124304) (elastic#124326)

Our check methods injected by the instrumenter receive "this" as the second parameter.
For internal classes like AbstractDelegateHttpsURLConnection we generally use a base type; in this case we were using javax.net.ssl.HttpsURLConnection, which is incorrect as AbstractDelegateHttpsURLConnection derives from java.net.HttpURLConnection.
This was not failing in our tests because we don't actually use that parameter in that check function.

Also, it was not failing on transform, just on retransformClasses, and only in JDK 24. Apparently, JDK 24 introduced new validation there (to be confirmed).

And it was failing just on cloud as the APM agent there (which is loaded before our agent) connects to a https endpoint - our IT tests, and ./gradlew run --with-apm-server, use a http endpoint. Using https makes the JVM load AbstractDelegateHttpsURLConnection, making it one of the classes we need to retransform, triggering the VerifyError.

Author: ldematte

libs/entitlement/bridge/src/main/java/org/elasticsearch/entitlement/bridge/EntitlementChecker.java

@@ -510,10 +510,7 @@ public interface EntitlementChecker {
         Class<?>[] classes
     );
 
-    void check$sun_net_www_protocol_https_AbstractDelegateHttpsURLConnection$connect(
-        Class<?> callerClass,
-        javax.net.ssl.HttpsURLConnection that
-    );
+    void check$sun_net_www_protocol_https_AbstractDelegateHttpsURLConnection$connect(Class<?> callerClass, java.net.HttpURLConnection that);
 
     void check$sun_net_www_protocol_mailto_MailToURLConnection$connect(Class<?> callerClass, java.net.URLConnection that);
 

libs/entitlement/src/main/java/org/elasticsearch/entitlement/runtime/api/ElasticsearchEntitlementChecker.java

@@ -1172,7 +1172,7 @@ private static boolean isFileUrlConnection(java.net.URLConnection urlConnection)
     @Override
     public void check$sun_net_www_protocol_https_AbstractDelegateHttpsURLConnection$connect(
         Class<?> callerClass,
-        javax.net.ssl.HttpsURLConnection that
+        java.net.HttpURLConnection that
     ) {
         policyManager.checkOutboundNetworkAccess(callerClass);
     }