"More information" link in OnionShare settings doesn't open

In a64f183bae:

1. Open OnionShare
2. Open the Settings dialog
3. Click on “More information”
4. Nothing happens

Feature Branch: bugfix/16914-onionshare-xdg-open

Related issues

• Related to #16913
• Blocks #16209

Original created by @sajolida on 16914 (Redmine)