Apparently, the Zulip notifications (and resulting emails) were
correct, but the download links inside the Zulip UI were incorrectly
not including S3 prefix on the URL, making them not work.
While we're at this, we rewrite the somewhat convoluted previous
system for formatting the data export output.
There was a bug where the success banner stuck
around even after the export completed. We now
nicely fade and remove the banner upon a successful
population of the export in the table.
Fixes: #13045
02cfb47 removed a couple HTML tags that were
being used to sort the table. We fix this,
but disable filtering exports by marking the
input type as `hidden`. We use this approach as
it seems `list_render` doesn't like an
undefined `opts.filter.element`, which is
what happens if we simply remove the `filter`
key.
