fix: bail if --chaos and specific version

See coop-cloud/organising#503.

cli/app/rollback.go

@@ -51,6 +51,11 @@ recipes.
 		app := internal.ValidateApp(c)
 		stackName := app.StackName()
 
+		specificVersion := c.Args().Get(1)
+		if specificVersion != "" && internal.Chaos {
+			logrus.Fatal("cannot use <version> and --chaos together")
+		}
+
 		if err := recipe.EnsureExists(app.Recipe); err != nil {
 			logrus.Fatal(err)
 		}
@@ -125,7 +130,6 @@ recipes.
 			logrus.Warnf("failed to determine deployed version of %s", app.Name)
 		}
 
-		specificVersion := c.Args().Get(1)
 		if specificVersion != "" {
 			parsedDeployedVersion, err := tagcmp.Parse(deployedVersion)
 			if err != nil {