Do not try to get the jailed path if we can't find the id
Do not try to get the jailed path if we can't find the id

Fixes #8047

If we can't find the file by id there we should just return null instead
of trying to get the jailed path of null.

Signed-off-by: Roeland Jago Douma <982d370f7dc34a05b4abe8788f899578d515262d@famdouma.nl>

nextcloud/server,michaelletzgus/nextcloud-server,nextcloud/server,andreas-p/nextcloud-server,andreas-p/nextcloud-server,nextcloud/server,andreas-p/nextcloud-server,andreas-p/nextcloud-server,michaelletzgus/nextcloud-server,andreas-p/nextcloud-server,michaelletzgus/nextcloud-server,nextcloud/server,michaelletzgus/nextcloud-server