Default mail language fallback is not working

[case0sh]

Describe the bug

Default mail language fallback is not working as expected

Steps to reproduce

Steps to reproduce the behavior:

1. set "SETTINGS_DEFAULT_LANGUAGE" env to "de"
2. set userB language to "Czech"
3. login as UserA and trigger a mail notification for userB by sharing a file

Expected behavior

If there no Czech email template it should fallback the default value "SETTINGS_DEFAULT_LANGUAGE"

Actual behavior

Fallback to English

Setup

You can use this docker compose
https://github.com/owncloud/ocis/blob/master/deployments/examples/ocis_traefik/docker-compose.yml
with latest master of oCIS

[2403905]

@case0sh Please note that the SETTINGS_DEFAULT_LANGUAGE changed to the global OCIS_DEFAULT_LANGUAGE.
Please read the fix description.

[case0sh]

fixed owncloud/ocis-charts#408