transmission: Permission denied when trying to write to Samba share after reboot

As reported https://discuss.freedombox.org/t/transmission-samba-open-share-permission-denied-message-on-reboot/1461.

Seems that the transmission-daemon service starts before the nslcd service. As a result the debian-transmission user doesn't belong to the freedombox-share group, which is defined in LDAP.

$ systemctl status nslcd | grep Active
     Active: active (running) since Tue 2021-03-02 11:20:22 EET; 18s ago

$ systemctl status transmission-daemon.service | grep Active
     Active: active (running) since Tue 2021-03-02 11:20:20 EET; 31s ago

# The transmission-daemon service belongs to only one group:
$ cat /proc/139/status | grep Groups                                                                                          
Groups: 120

# After restarting the transmission-daemon service:
$ cat /proc/1206/status | grep Groups                                               
Groups: 120 10001