Discovered while testing IBX-4581. 
In \eZ\Bundle\EzPublishCoreBundle\EventListener\ConsoleCommandListener::onConsoleCommand:

$this->siteAccess->name = $event->getInput()->getParameterOption('--siteaccess', $this->defaultSiteAccessName);
$this->siteAccess->matchingType = 'cli';
  

The above code doesn't really set SiteAccess based on the passed --siteaccess option, but just changes it's name. So, if passed SiteAccess has different group, the information set is going to be incorrect.

Steps to reproduce:

1. Create a CLI Symfony Command and inject SiteAccessServiceInterface
2. In the command execute method dump contents of $this->siteAccessService->getCurrent() method.
3. Call the command with --siteaccess=admin switch

Actual result:
Observe that groups are either empty (pre IBX-4581 fix) or contain site group coming from default SiteAccess.

Expected result
Observe that groups contain admin_group