fix code style introduce by #22983

Author: shibd

pulsar-client/src/main/java/org/apache/pulsar/client/impl/PulsarClientImpl.java

@@ -51,7 +51,6 @@
 import javax.annotation.Nullable;
 import lombok.Builder;
 import lombok.Getter;
-import org.apache.commons.lang3.tuple.Pair;
 import org.apache.pulsar.client.admin.PulsarAdminException;
 import org.apache.pulsar.client.api.Authentication;
 import org.apache.pulsar.client.api.Consumer;