Change all references to Domain Registry to Nomulus

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=136068582

java/google/registry/config/TestRegistryConfig.java

@@ -109,7 +109,7 @@ public class TestRegistryConfig implements RegistryConfig {
 
   @Override
   public String getGoogleAppsAdminEmailDisplayName() {
-    return "Testing Domain Registry";
+    return "Testing Nomulus";
   }
 
   @Override