David Gnedt befffa926b Fix concatenation of additional databases ...

Otherwise the postgres upgrade fails with the following error:

Unexpected templating type error occurred on ({{
  [matrix_postgres_connection_username]
  +
  matrix_postgres_additional_databases|map(attribute='username')
}}
): can only concatenate list (not "generator") to list

2020-12-23 19:24:45 +01:00

..

matrix_servers

Fix concatenation of additional databases

2020-12-23 19:24:45 +01:00