Update example docker setup

[eritikass]

same as privacyidea/privacyidea#2145

/cc @cornelinux

[cornelinux]

@plettich Can you please take a look at it, when you have the time.

[eritikass]

@plettich Can you please take a look at it, when you have the time.

@cornelinux any updates? all i can see is thumbs-up in your question

[plettich]

Hi @eritikass, sorry for the delay but as You can imagine, the docker setup is currently not a high priority.
I created issue #6 to discuss a more broad approach.