Expose encrypted data from the keyring

This makes it possible to request the encrypted data directly in application code. It will be used to download service account credential during "nomulus login".

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=222847905

java/google/registry/keyring/api/KeyModule.java

@@ -20,6 +20,8 @@ import dagger.Module;
 import dagger.Provides;
 import java.lang.annotation.Documented;
 import java.util.Optional;
+import java.util.function.Function;
+import javax.inject.Named;
 import javax.inject.Qualifier;
 import org.bouncycastle.openpgp.PGPKeyPair;
 import org.bouncycastle.openpgp.PGPPrivateKey;
@@ -126,4 +128,10 @@ public final class KeyModule {
   static String provideJsonCredential(Keyring keyring) {
     return keyring.getJsonCredential();
   }
+
+  @Provides
+  @Named("encryptedDataRetriever")
+  static Function<String, String> provideEncryptedDataRetriever(Keyring keyring) {
+    return keyring::getEncryptedData;
+  }
 }