Remove deprecated containerd.WithSchema1Conversion from host-ctr

[jpculp]

WithSchema1Conversion is used to convert Docker registry schema 1 manifests to oci manifests on pull. Without this option schema 1 manifests will return a not supported error. This is no deprecated and it is recommended to use schema 2 or OCI images.

Platform I'm building on:

N/A

What I expected to happen:

host-ctr to pass lints

What actually happened:

cmd/host-ctr/main.go:1053:4: SA1019: containerd.WithSchema1Conversion is deprecated: use Schema 2 or OCI images. (staticcheck)
			containerd.WithSchema1Conversion,

How to reproduce the problem:

Remove the exception added to host-ctr/main.go and run golangci-lint.