Remove unnecessary "throws" declarations

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=201058582

java/google/registry/rde/JSchSshSession.java

@@ -23,7 +23,6 @@ import com.jcraft.jsch.Session;
 import com.jcraft.jsch.SftpException;
 import google.registry.config.RegistryConfig.Config;
 import java.io.Closeable;
-import java.io.IOException;
 import java.net.URI;
 import javax.inject.Inject;
 import org.joda.time.Duration;
@@ -118,7 +117,7 @@ final class JSchSshSession implements Closeable {
 
   /** @see com.jcraft.jsch.Session#disconnect() */
   @Override
-  public void close() throws IOException {
+  public void close() {
     session.disconnect();
   }
 }