fix(setup): stop redirect after CAN_INSTALL removal failure

Signed-off-by: Josh <josh.t.richards@gmail.com>

Author: joshtrichards

core/Controller/SetupController.php

@@ -114,6 +114,7 @@ private function finishSetup(): void {
 
 		if ($this->setupHelper->shouldRemoveCanInstallFile()) {
 			$this->templateManager->printGuestPage('', 'installation_incomplete');
+			return;
 		}
 
 		header('Location: ' . Server::get(IURLGenerator::class)->getAbsoluteURL('index.php/core/apps/recommended'));