fix: gatsby swag revival - 3

updated data.json for 'gatsby x netlify' swag
- updated the swag img url
- added mug in tag section

data.json

@@ -427,9 +427,9 @@
     "difficulty": "hard",
     "description": "Get a pull request merged into Gatsby and receive a free shirt, socks, or stickers.",
     "reference": "https://www.gatsbyjs.com/contributing/contributor-swag/",
-    "image": "https://i.imgur.com/e7GwaTN.png",
+    "image": "https://cdn.shopify.com/s/files/1/0332/2730/9195/products/Shirt.png?v=1677684481&width=600&height=",
     "dateAdded": "2024-10-04T16:08:09.000Z",
-    "tags": ["clothing", "stickers"]
+    "tags": ["clothing", "stickers", "mug"]
   },
   {
     "name": "GeeksForGeeks",