Show message when list-releases is called from within a UKI OS

Consume https://github.com/kairos-io/kairos-sdk/pull/262/files

Signed-off-by: Dimitris Karakasilis <dimitris@karakasilis.me>

main.go

@@ -99,6 +99,13 @@ See https://kairos.io/docs/upgrade/manual/ for documentation.
 				Name:        "list-releases",
 				Description: `List all available releases versions`,
 				Action: func(c *cli.Context) error {
+					if utils.IsUki() {
+						fmt.Println("You are running in \"trusted boot\" mode")
+						fmt.Println("Upgrading your OS requires a new image to be built an signed")
+						fmt.Println("Read the docs on how to do so: https://kairos.io/docs/upgrade/trustedboot/")
+						return nil
+					}
+
 					currentImage, err := agent.CurrentImage()
 					if err != nil {
 						return err