Improve download of PopulationData

[patricklnz]

Motivation / Current Behaviour

CI fails often. Twill package breaks easily

Enhancement description

use some kind of requests with authentification

check https://www.regionalstatistik.de/genesis/misc/Deep-Links_REG.pdf for deep link downloads.

Additional context

No response

Checklist

• [X] Attached labels, especially loc:: or model:: labels.
• [X] Linked to project