fix: [twitter-post] underscore - minus are difficult to choose from ;-)

Author: adulau

objects/twitter-post/definition.json

@@ -80,7 +80,7 @@
     },
     "media": {
       "description": "Media (Photos, videos) present in tweet",
-      "misp_attribute": "attachment",
+      "misp-attribute": "attachment",
       "multiple": true,
       "ui-priority": 0
     },
@@ -160,4 +160,4 @@
   ],
   "uuid": "d1214031-ce1b-4a35-bd33-644c707bda2e",
   "version": 5
-}
+}