sponsors: Add Blacksmith

Since Blacksmith has sponsored us with a service they provide instead of
a regular tiered sponsorship, we introduce a new section called
"Infrastructure Sponsors".

Author: gmta

public/assets/img/sponsor-blacksmith.svg

@@ -175,6 +175,16 @@ const sponsors = [
       },
     ],
   },
+  {
+    name: "Infrastructure Sponsors",
+    sponsors: [
+      {
+        name: "Blacksmith",
+        href: "https://www.blacksmith.sh",
+        logo: "/assets/img/sponsor-blacksmith.svg",
+      },
+    ],
+  },
 ];
 ---