mediawiki: turn on captcha to prevent spam

hosts/containers/mediawiki/default.nix

@@ -151,6 +151,10 @@ in
         $wgGroupPermissions['sysop']['deletelogentry'] = true;
         $wgGroupPermissions['sysop']['deleterevision'] = true;
 
+        wfLoadExtension('ConfirmEdit/QuestyCaptcha');
+        $wgCaptchaClass = 'QuestyCaptcha';
+        $wgCaptchaQuestions[] = array( 'question' => 'How is C3D2 logo in ascii?', 'answer' => '<<</>>' );
+
         $wgEnableAPI = true;
         $wgAllowUserCss = true;
         $wgUseAjax = true;