let's encrypt fix

[priamai]

The script uses an old syntax, it should be updated with this:

# Generate the cert and save it to the Docker volume
docker run --rm -it \
  -p 80:80 \
  -v $SECRETS_VOLUME:/etc/letsencrypt \
  quay.io/letsencrypt/letsencrypt:latest \
  certonly \
  --non-interactive \
  --keep-until-expiring \
  --standalone \
  --preferred-challenges http-01 \
  --agree-tos \
  --force-renewal \
  --domain "$FQDN" \
  --email "$EMAIL" \
  $CERT_SERVER

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[manics]

Let-encrypt was removed to simplify maintenance