channel.db is not accessible by jet on RaspiBlitz

[itsneski]

Jet monitors the size of channel.db and notifies via telegram when the size goes over a limit. On RaspiBlitz, channel.db runs from the bitcoin:bitcoin account, whereas jet runs from the bos (BalanceOfSatoshis) account. Subsequently, jet does not have read access to the channel.db and can not notify via telegram when the channel.db size goes over the limit.