Update dataset_infos.json

dataset_infos.json

@@ -5,8 +5,8 @@
     "homepage": "https://github.com/Hyphonical/civistash",
     "license": "other",
     "features": {
-      "json": {
-        "_type": "Json"
+      "jpg": {
+        "_type": "Image"
       }
     }
   }