Add Cloud Pub/Sub to Google external technology

README.md

@@ -17,7 +17,7 @@ See also: [System Design Primer](https://github.com/donnemartin/system-design-pr
 | Protocol Buffer | [Protobuf](https://github.com/google/protobuf) | [Cap'n Proto](https://capnproto.org/), [Thrift](https://github.com/apache/thrift), [Avro](https://github.com/apache/avro), [Amazon Ion](https://amzn.github.io/ion-docs/), [CBOR](https://cbor.io/), [kryo](https://github.com/EsotericSoftware/kryo) |
 | Stubby          | [gRPC](https://github.com/grpc/grpc)     | [Thrift](https://github.com/apache/thrift), [Bolt](https://boltprotocol.org/) |
 | Chubby          |                                          | [Apache Zookeeper](https://github.com/apache/zookeeper), [etcd](https://github.com/coreos/etcd), [HashiCorp Consul](https://github.com/hashicorp/consul) |
-| Goops / PubSub  |                                          | [Apache Kafka](https://github.com/apache/kafka), [Apache Pulsar](https://github.com/apache/incubator-pulsar), [Facebook LogDevice](https://github.com/facebookincubator/LogDevice) |
+| Goops / PubSub  | [Cloud Pub/Sub](https://cloud.google.com/pubsub)     | [Apache Kafka](https://github.com/apache/kafka), [Apache Pulsar](https://github.com/apache/incubator-pulsar), [Facebook LogDevice](https://github.com/facebookincubator/LogDevice) |
 | `//base`        |                                          | [abseil](https://github.com/abseil) |
 
 ### Infrastructure