feat: replace `curl_upload` with `curl_upload_file`

BREAKING CHANGE: `curl_upload` is removed, long live `curl_upload_file`.

We hope to add `curl_upload` back in to allow uploads of multiple files.

There are complexities due to the correct mapping of filepaths.

It may be that packaging multiple files into a archive with `rules_pkg`
and then uploading that archive is a better way forward anyway.