JettyServer: Stop using deprecated SslContextFactory constructor

Use SslContextFactory.Server instead, as recommended.

Change-Id: If2eb77d6bc6bfcd26e69dd42e35bfa885440da9e
diff --git a/java/com/google/gerrit/pgm/http/jetty/JettyServer.java b/java/com/google/gerrit/pgm/http/jetty/JettyServer.java
index 7745ad4..22bc21d 100644
--- a/java/com/google/gerrit/pgm/http/jetty/JettyServer.java
+++ b/java/com/google/gerrit/pgm/http/jetty/JettyServer.java
@@ -196,7 +196,7 @@
         c = newServerConnector(server, acceptors, config);
 
       } else if ("https".equals(u.getScheme())) {
-        SslContextFactory ssl = new SslContextFactory();
+        SslContextFactory.Server ssl = new SslContextFactory.Server();
         final Path keystore = getFile(cfg, "sslkeystore", "etc/keystore");
         String password = cfg.getString("httpd", null, "sslkeypassword");
         if (password == null) {