Derive RDAP link paths from the received query

The former method -- a config string -- was cumbersome, as each Nomulus system would have to configure the link base to its own URL.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=173567021

java/google/registry/config/RegistryConfigSettings.java

@@ -32,7 +32,6 @@ public class RegistryConfigSettings {
   public RegistrarConsole registrarConsole;
   public Monitoring monitoring;
   public Misc misc;
-  public Rdap rdap;
   public Braintree braintree;
   public Kms kms;
   public RegistryTool registryTool;
@@ -148,11 +147,6 @@ public class RegistryConfigSettings {
     public String sheetExportId;
   }
 
-  /** Configuration for RDAP. */
-  public static class Rdap {
-    public String baseUrl;
-  }
-
   /** Configuration for Braintree credit card payment processing. */
   public static class Braintree {
     public String merchantId;