Bump github.com/containers/storage from 1.20.2 to 1.21.0

Bumps [github.com/containers/storage](https://github.com/containers/storage) from 1.20.2 to 1.21.0.
- [Release notes](https://github.com/containers/storage/releases)
- [Changelog](https://github.com/containers/storage/blob/master/docs/containers-storage-changes.md)
- [Commits](https://github.com/containers/storage/compare/v1.20.2...v1.21.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

vendor/github.com/opencontainers/selinux/go-selinux/doc.go

@@ -0,0 +1,21 @@
+/*
+Package selinux provides a high-level interface for interacting with selinux.
+
+This package uses a selinux build tag to enable the selinux functionality. This
+allows non-linux and linux users who do not have selinux support to still use
+tools that rely on this library.
+
+To compile with full selinux support use the -tags=selinux option in your build
+and test commands.
+
+Usage:
+
+	import "github.com/opencontainers/selinux/go-selinux"
+
+	// Ensure that selinux is enforcing mode.
+	if selinux.EnforceMode() != selinux.Enforcing {
+		selinux.SetEnforceMode(selinux.Enforcing)
+	}
+
+*/
+package selinux