fix: Consider app transfer as a valid command (#49)

App ownership transfer from CLI always shows help, rather than doing
action. It seems command is never marked as valid.

cli/script/command-parser.ts

@@ -322,6 +322,7 @@ yargs
       .command("list", "Lists the apps associated with your account", (yargs: yargs.Argv) => appList("list", yargs))
       .command("ls", "Lists the apps associated with your account", (yargs: yargs.Argv) => appList("ls", yargs))
       .command("transfer", "Transfer the ownership of an app to another account", (yargs: yargs.Argv) => {
+        isValidCommand = true;
         yargs
           .usage(USAGE_PREFIX + " app transfer <appName> <email>")
           .demand(/*count*/ 2, /*max*/ 2) // Require exactly two non-option arguments