Move ROID suffix handling from RegistryConfig to ConfigModule

This is the first in a decently long series of commits to delete RegistryConfig
entirely and centralize all configuration in ConfigModule using Dagger. Once
this is done, then the text-based YAML configuration work can begin in earnest.

Note that the configuration settings from TestRegistryConfig will be moving
into ConfigModule.LocalTestConfig. This way they can be referred to in a static
context from test and test utility helpers, rather than having to be injected
everywhere, which we don't typically bother with for tests.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=143473089

java/google/registry/config/ProductionRegistryConfigExample.java

@@ -158,11 +158,6 @@ public final class ProductionRegistryConfigExample implements RegistryConfig {
     return Duration.millis(100);
   }
 
-  @Override
-  public String getContactAndHostRepositoryIdentifier() {
-    return "ROID";
-  }
-
   @Override
   public Duration getContactAutomaticTransferLength() {
     return standardDays(5);