Bump github.com/containers/common from 0.20.3 to 0.21.0

Bumps [github.com/containers/common](https://github.com/containers/common) from 0.20.3 to 0.21.0.
- [Release notes](https://github.com/containers/common/releases)
- [Commits](https://github.com/containers/common/compare/v0.20.3...v0.21.0)

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

vendor/github.com/containers/storage/pkg/mount/mount.go

@@ -4,8 +4,6 @@ import (
 	"sort"
 	"strconv"
 	"strings"
-
-	"github.com/containers/storage/pkg/fileutils"
 )
 
 // mountError holds an error from a mount or unmount operation
@@ -43,33 +41,6 @@ func (e *mountError) Cause() error {
 	return e.err
 }
 
-// GetMounts retrieves a list of mounts for the current running process.
-func GetMounts() ([]*Info, error) {
-	return parseMountTable()
-}
-
-// Mounted determines if a specified mountpoint has been mounted.
-// On Linux it looks at /proc/self/mountinfo and on Solaris at mnttab.
-func Mounted(mountpoint string) (bool, error) {
-	entries, err := parseMountTable()
-	if err != nil {
-		return false, err
-	}
-
-	mountpoint, err = fileutils.ReadSymlinkedPath(mountpoint)
-	if err != nil {
-		return false, err
-	}
-
-	// Search the table for the mountpoint
-	for _, e := range entries {
-		if e.Mountpoint == mountpoint {
-			return true, nil
-		}
-	}
-	return false, nil
-}
-
 // Mount will mount filesystem according to the specified configuration, on the
 // condition that the target path is *not* already mounted. Options must be
 // specified like the mount or fstab unix commands: "opt1=val1,opt2=val2". See