client/v3/README.md: Remove warning
go get go.etcd.io/etcd/client/v3
```
-Warning: As etcd 3.5.0 was not yet released, the command above does not work.
-After first pre-release of 3.5.0 [#12498](https://github.com/etcd-io/etcd/issues/12498),
-etcd can be referenced using:
-```
-go get go.etcd.io/etcd/client/v3@v3.5.0-pre
-```
-
## Get started
Create client using `clientv3.New`:
```go
+import clientv3 "go.etcd.io/etcd/client/v3"
+
+func main() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: []string{"localhost:2379", "localhost:22379", "localhost:32379"},
DialTimeout: 5 * time.Second,
@@ -31,6 +27,7 @@ if err != nil {
// handle error!
}
defer cli.Close()
+}
```
etcd v3 uses [`gRPC`](https://www.grpc.io) for remote procedure calls. And `clientv3` uses
