Close etcd clients to avoid leaking GRPC connections

If you don't explicitly close the etcd client when you're done with it,
the GRPC connection hangs around in the background. Normally this is
harmelss, but in the case of the temporary etcd we start up on 2399 to
reconcile bootstrap data, the client will start logging errors
afterwards when the server goes away.

Signed-off-by: Brad Davidson <brad.davidson@rancher.com>

pkg/cluster/bootstrap.go

@@ -393,6 +393,7 @@ func (c *Cluster) ReconcileBootstrapData(ctx context.Context, buf io.ReadSeeker,
 		if err != nil {
 			return err
 		}
+		defer storageClient.Close()
 
 		ticker := time.NewTicker(5 * time.Second)
 		defer ticker.Stop()

pkg/cluster/storage.go

@@ -48,6 +48,7 @@ func Save(ctx context.Context, config *config.Control, etcdConfig endpoint.ETCDC
 	if err != nil {
 		return err
 	}
+	defer storageClient.Close()
 
 	if _, _, err = getBootstrapKeyFromStorage(ctx, storageClient, normalizedToken, token); err != nil {
 		return err
@@ -102,6 +103,7 @@ func (c *Cluster) storageBootstrap(ctx context.Context) error {
 	if err != nil {
 		return err
 	}
+	defer storageClient.Close()
 
 	token := c.config.Token
 	if token == "" {