PHP Fatal Error: Return value of LocalSetup::execute must be of the type int, "NULL" returned.

[dungahk]

I'm getting this error message when trying to run dorgflow {ISSUE_URL}:

Hello, this is Dorgflow!
Detected master branch 8.x-1.x.
Fetching node 3132912 from drupal.org.
Created feature branch 3132912-Override-getIdealConditionsLimit-and-make-it-configurable.
There are no patches to apply.
PHP Fatal error:  Uncaught TypeError: Return value of "Dorgflow\Command\LocalSetup::execute()" must be of the type int, "NULL" returned. in /home/emerson/drupal/contrib/dorgflow/vendor/symfony/console/Command/Command.php:258
Stack trace:
#0 /home/emerson/drupal/contrib/dorgflow/vendor/symfony/console/Application.php(912): Symfony\Component\Console\Command\Command->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#1 /home/emerson/drupal/contrib/dorgflow/vendor/symfony/console/Application.php(264): Symfony\Component\Console\Application->doRunCommand(Object(Dorgflow\Command\LocalSetup), Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#2 /home/emerson/drupal/contrib/dorgflow/vendor/symfony/console/Application.php(140): Symfony\Component\Console\Application->doRun(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#3 /home/emerson/drupal/contrib/dorgflow/dor in /home/emerson/drupal/contrib/dorgflow/vendor/symfony/console/Command/Command.php on line 258

php --version

PHP 7.2.29-1+ubuntu18.04.1+deb.sury.org+1 (cli) (built: Mar 20 2020 13:54:39) ( NTS )
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