Bump ttrpc

Co-authored-by: Giuseppe Capizzi <gcapizzi@pivotal.io>
Signed-off-by: Georgi Sabev <georgethebeatle@gmail.com>

vendor/github.com/containerd/ttrpc/server.go

@@ -449,7 +449,12 @@ func (c *serverConn) run(sctx context.Context) {
 			// branch. Basically, it means that we are no longer receiving
 			// requests due to a terminal error.
 			recvErr = nil // connection is now "closing"
-			if err != nil && err != io.EOF {
+			if err == io.EOF || err == io.ErrUnexpectedEOF {
+				// The client went away and we should stop processing
+				// requests, so that the client connection is closed
+				return
+			}
+			if err != nil {
 				logrus.WithError(err).Error("error receiving message")
 			}
 		case <-shutdown: