Applies perfsprint linter (#24999)

Replacing usages of fmt.Sprint with faster alternatives

Signed-off-by: Philippe Antoine <contact@catenacyber.fr>

server/cmd/mmctl/commands/utils_unix.go

@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"os"
 	"os/user"
+	"strconv"
 	"syscall"
 
 	"github.com/isacikgoz/prompt"
@@ -38,7 +39,7 @@ func checkValidSocket(socketPath string) error {
 		return fmt.Errorf("cannot get owner of the file %q", socketPath)
 	}
 	// if user id is "0", they are root and we should avoid this check
-	if fmt.Sprint(s.Uid) != cUser.Uid && cUser.Uid != "0" {
+	if strconv.FormatUint(uint64(s.Uid), 10) != cUser.Uid && cUser.Uid != "0" {
 		return fmt.Errorf("owner of the file %q must be the same user running mmctl", socketPath)
 	}