Map data in Kommunalwahlen 2020 don't load on page load

[FloEdelmann]

Steps to reproduce:

1. Go to https://vaterstetten-in-zahlen.de/?tab=kommunalwahl2020 (directly or via an in-app link)
2. See this result:
   
3. See these console errors:
   

Changing any dropdown loads the map data as expected, also changing it back to the default value works.

[fxedel]

Finally had some time to fix this. It seemed to be a kind of timing problem / race condition, since the map is not initialized with render() when the print function tries to find the map by its id and update its layers.