Update github.com/containerd/containerd to fix security vulnerability

See: https://nvd.nist.gov/vuln/detail/CVE-2021-32760

go.mod

@@ -1,35 +1,14 @@
 module github.com/dhui/dktest
 
 require (
-	github.com/Azure/go-ansiterm v0.0.0-20170929234023-d6e3b3328b78 // indirect
-	github.com/Microsoft/go-winio v0.4.16 // indirect
-	github.com/containerd/containerd v1.4.3 // indirect
-	github.com/docker/distribution v2.7.1+incompatible // indirect
+	github.com/containerd/containerd v1.5.4 // indirect
 	github.com/docker/docker v17.12.0-ce-rc1.0.20210128214336-420b1d36250f+incompatible
 	github.com/docker/go-connections v0.4.0
-	github.com/docker/go-units v0.4.0 // indirect
-	github.com/gogo/protobuf v1.3.2 // indirect
-	github.com/golang/protobuf v1.4.3 // indirect
-	github.com/gorilla/context v1.1.1 // indirect
-	github.com/gorilla/mux v1.6.2 // indirect
-	github.com/konsorten/go-windows-terminal-sequences v1.0.3 // indirect
-	github.com/kr/pretty v0.1.0 // indirect
 	github.com/lib/pq v1.8.0
 	github.com/morikuni/aec v1.0.0 // indirect
-	github.com/opencontainers/go-digest v1.0.0 // indirect
-	github.com/opencontainers/image-spec v1.0.1 // indirect
-	github.com/pkg/errors v0.9.1 // indirect
-	github.com/sirupsen/logrus v1.7.0 // indirect
-	github.com/stretchr/testify v1.5.1
-	golang.org/x/net v0.0.0-20210119194325-5f4716e94777 // indirect
-	golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c // indirect
-	golang.org/x/time v0.0.0-20181108054448-85acf8d2951c // indirect
+	github.com/stretchr/testify v1.6.1
 	google.golang.org/genproto v0.0.0-20210207032614-bba0dbe2a9ea // indirect
 	google.golang.org/grpc v1.35.0 // indirect
-	google.golang.org/protobuf v1.25.0 // indirect
-	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
-	gopkg.in/yaml.v2 v2.2.8 // indirect
-	gotest.tools v2.2.0+incompatible // indirect
 )
 
 go 1.13