Docker: pgadmin cannot start because some variables are missing

[frafra]

You need to define the PGADMIN_DEFAULT_EMAIL and PGADMIN_DEFAULT_PASSWORD environment variables.

This happens because these environmental variables are not set in docker-compose.yml:

https://github.com/OpenKnowledgeMaps/Headstart/blob/80274329374d1c5bdc7cfc4a7cdca16ddb45b807/docker-compose.yml#L9-L11