ES: Temporarily disable server discovery

When server discovery is enabled Gerrit will fail to run off-line reindex
and start up. The reason behind it is that we are trying to use JEST
client without assigned servers - the discovery process has not yet
finished.

Therefore for now we should disable this feature and enable it again
when we are able to wait until this discovery process finishes.

Change-Id: Ia89b7c072a5a4e898c29fd0d18d6ce4385fee4e7

gerrit-elasticsearch/src/main/java/com/google/gerrit/elasticsearch/JestClientBuilder.java

@@ -60,7 +60,9 @@ class JestClientBuilder {
     factory.setHttpClientConfig(
         new HttpClientConfig.Builder(url)
             .multiThreaded(true)
-            .discoveryEnabled(!refresh)
+            // Temporary disable servers discovery.
+            // We can enable it again when we can wait for it to finish
+            .discoveryEnabled(false)
             .discoveryFrequency(1L, TimeUnit.MINUTES)
             .build());
     return (JestHttpClient) factory.getObject();