Use -dot- subdomain notation in MapReduce console links

appspot.com is not provisioned with a multi-level wildcard SSL certificate, so
URLs of the form https://service.projectid.appspot.com/path need to be rewritten
as https://service-dot-projectid.appspot.com/path (and same for version names).

This is a follow-up to []

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=231418795

javatests/google/registry/tools/server/GenerateZoneFilesActionTest.java

@@ -132,7 +132,8 @@ public class GenerateZoneFilesActionTest extends MapreduceTestCase<GenerateZoneF
     assertThat(response).containsKey("mapreduceConsoleLink");
     assertThat(response.get("mapreduceConsoleLink").toString())
         .startsWith(
-            "Mapreduce console: https://backend.hostname.tld/_ah/pipeline/status.html?root=");
+            "Mapreduce console: https://backend-dot-projectid.appspot.com"
+                + "/_ah/pipeline/status.html?root=");
 
     executeTasksUntilEmpty("mapreduce");