Fix dep init outside of git (#2338)
Fix dep init outside of git (#2338)

If it is set to null, an error will occur in other processing,
 so it was initialized with an empty string.

SymfonyStyle#ask is v5 with type-hint added.
`$default` is ?string so bool is not acceptable.

https://github.com/symfony/symfony/blob/5.x/src/Symfony/Component/Console/Style/SymfonyStyle.php#L267
deployphp/deployer,deployphp/deployer,deployphp/deployer