/etc/default/go-server needs to be exposed by a volume

[EugenMayer]

Since a lot of server-side configuration like

• https://docs.go.cd/16.1.0/installation/ssl_tls_config.html
• https://docs.go.cd/current/beta/plugin_upload.html

does go into https://docs.go.cd/16.1.0/installation/ssl_tls_config.html this file needs to be persistent over container rebuilds