nydusify: fix unnecessary golang-lint error

```
golangci-lint run
Error: pkg/converter/provider/ported.go:47:64: SA1019: rCtx.ConvertSchema1 is deprecated: use Schema 2 or OCI images. (staticcheck)
	if desc.MediaType == images.MediaTypeDockerSchema1Manifest && rCtx.ConvertSchema1 {
	                                                              ^
Error: pkg/converter/provider/ported.go:20:2: SA1019: "github.com/containerd/containerd/remotes/docker/schema1" is deprecated: use images formatted in Docker Image Manifest v2, Schema 2, or OCI Image Spec v1. (staticcheck)
	"github.com/containerd/containerd/remotes/docker/schema1"
	^
```

Disabled the check, it's unnecessary to check the ported codes.

Signed-off-by: Yan Song <imeoer@linux.alibaba.com>

contrib/nydusify/pkg/converter/provider/ported.go

@@ -17,6 +17,8 @@ import (
 	"github.com/containerd/containerd/platforms"
 	"github.com/containerd/containerd/remotes"
 	"github.com/containerd/containerd/remotes/docker"
+
+	// nolint:staticcheck
 	"github.com/containerd/containerd/remotes/docker/schema1"
 	"github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
@@ -44,6 +46,7 @@ func fetch(ctx context.Context, store content.Store, rCtx *containerd.RemoteCont
 		limiter       *semaphore.Weighted
 	)
 
+	// nolint:staticcheck
 	if desc.MediaType == images.MediaTypeDockerSchema1Manifest && rCtx.ConvertSchema1 {
 		schema1Converter := schema1.NewConverter(store, fetcher)