(feat) Update sponsors page

Author: Weile-Zheng

config/sponsors.json

@@ -7,6 +7,11 @@
         "link": "https://www.myrocketcareer.com/",
         "image": "rocket.png"
       },
+      {
+        "name": "Discover",
+        "link": "https://www.discover.com/",
+        "image": "discover.png"
+      },
       {
         "name": "Wolverine Trading",
         "link": "https://www.wolve.com/",