Fixed failing test after drawio default url change

[bookstack] / dev / api / requests / pages-update.json

{
        "chapter_id": 1,
        "name": "My updated API Page",
        "html": "<p>my new API page - Updated</p>",
        "tags": [
                {"name": "Category", "value": "API Examples"},
                {"name": "Rating", "value": "Alright"}
        ]
}