Stop using math/rand.Read and rand.Seed (deprecated in Go 1.20)

From golangci-lint:

> SA1019: rand.Read has been deprecated since Go 1.20 because it
>shouldn't be used: For almost all use cases, crypto/rand.Read is more
>appropriate. (staticcheck)

> SA1019: rand.Seed has been deprecated since Go 1.20 and an alternative
>has been available since Go 1.0: Programs that call Seed and then expect
>a specific sequence of results from the global random source (using
>functions such as Int) can be broken when a dependency changes how
>much it consumes from the global random source. To avoid such breakages,
>programs that need a specific result sequence should use
>NewRand(NewSource(seed)) to obtain a random generator that other
>packages cannot access. (staticcheck)

See also:

- https://pkg.go.dev/math/rand@go1.20#Read
- https://pkg.go.dev/math/rand@go1.20#Seed

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

cmd/ctr/main.go

@@ -23,13 +23,14 @@ import (
 
 	"github.com/containerd/containerd/cmd/ctr/app"
 	"github.com/containerd/containerd/pkg/hasher"
-	"github.com/containerd/containerd/pkg/seed"
+	"github.com/containerd/containerd/pkg/seed" //nolint:staticcheck // Global math/rand seed is deprecated, but still used by external dependencies
 	"github.com/urfave/cli"
 )
 
 var pluginCmds = []cli.Command{}
 
 func init() {
+	//nolint:staticcheck // Global math/rand seed is deprecated, but still used by external dependencies
 	seed.WithTimeAndRand()
 	crypto.RegisterHash(crypto.SHA256, hasher.NewSHA256)
 }