refactor!: app name -> domain

cli/app/upgrade.go

@@ -21,7 +21,7 @@ var appUpgradeCommand = cli.Command{
 	Name:      "upgrade",
 	Aliases:   []string{"up"},
 	Usage:     "Upgrade an app",
-	ArgsUsage: "<app>",
+	ArgsUsage: "<domain>",
 	Flags: []cli.Flag{
 		internal.DebugFlag,
 		internal.NoInputFlag,
@@ -35,7 +35,7 @@ This command supports upgrading an app. You can use it to choose and roll out a
 new upgrade to an existing app.
 
 This command specifically supports incrementing the version of running apps, as
-opposed to "abra app deploy <app>" which will not change the version of a
+opposed to "abra app deploy <domain>" which will not change the version of a
 deployed app.
 
 You may pass "--force/-f" to upgrade to the same version again. This can be