Bump github.com/containerd/containerd in /test/docker

Bumps [github.com/containerd/containerd](https://github.com/containerd/containerd) from 1.6.6 to 1.6.18.
- [Release notes](https://github.com/containerd/containerd/releases)
- [Changelog](https://github.com/containerd/containerd/blob/main/RELEASES.md)
- [Commits](https://github.com/containerd/containerd/compare/v1.6.6...v1.6.18)

---
updated-dependencies:
- dependency-name: github.com/containerd/containerd
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>

test/docker/go.mod

@@ -19,8 +19,8 @@ require (
 
 require (
 	github.com/Azure/go-ansiterm v0.0.0-20230124172434-306776ec8161 // indirect
-	github.com/Microsoft/go-winio v0.5.1 // indirect
-	github.com/containerd/containerd v1.6.6 // indirect
+	github.com/Microsoft/go-winio v0.5.2 // indirect
+	github.com/containerd/containerd v1.6.18 // indirect
 	github.com/docker/distribution v2.8.1+incompatible // indirect
 	github.com/docker/go-units v0.4.0 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
@@ -31,10 +31,10 @@ require (
 	github.com/opencontainers/image-spec v1.0.3-0.20211202183452-c5a74bcca799 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/sirupsen/logrus v1.8.1 // indirect
-	golang.org/x/net v0.0.0-20211216030914-fe4d6282115f // indirect
-	golang.org/x/sys v0.0.0-20220422013727-9388b58f7150 // indirect
-	google.golang.org/genproto v0.0.0-20211208223120-3a66f561d7aa // indirect
-	google.golang.org/grpc v1.46.0 // indirect
-	google.golang.org/protobuf v1.27.1 // indirect
+	golang.org/x/net v0.0.0-20220722155237-a158d28d115b // indirect
+	golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f // indirect
+	google.golang.org/genproto v0.0.0-20220502173005-c8bf987b8c21 // indirect
+	google.golang.org/grpc v1.47.0 // indirect
+	google.golang.org/protobuf v1.28.0 // indirect
 	gotest.tools v2.2.0+incompatible // indirect
 )