curl --request POST \
  --url https://api.mudstack.com/workspaces/import/upload/begin \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'x-account-id: <x-account-id>' \
  --header 'x-workspace-id: <x-workspace-id>' \
  --data '{
  "file_sha": "<string>"
}'

{
  "signedUrl": "<string>"
}