Change wording of the “undo” media upload button (fixes #6857) (#7417)

app/javascript/mastodon/locales/defaultMessages.json

@@ -819,7 +819,7 @@
         "id": "upload_form.description"
       },
       {
-        "defaultMessage": "Undo",
+        "defaultMessage": "Delete",
         "id": "upload_form.undo"
       },
       {
@@ -1857,4 +1857,4 @@
     ],
     "path": "app/javascript/mastodon/features/video/index.json"
   }
-]
+]

app/javascript/mastodon/locales/en.json

@@ -283,7 +283,7 @@
   "upload_button.label": "Add media",
   "upload_form.description": "Describe for the visually impaired",
   "upload_form.focus": "Crop",
-  "upload_form.undo": "Undo",
+  "upload_form.undo": "Delete",
   "upload_progress.label": "Uploading...",
   "video.close": "Close video",
   "video.exit_fullscreen": "Exit full screen",