feeadjuster setting base fees of 1000 msats even though fee-base is set to 0

[dazl]

After updating CLN to v23.05

with no other config changes

fee adjuster now sets base fees of 1000 msats for all channels

before updating it would adjust ppm fees but leave base fees unchanged at zero.

$ lightning-cli listconfigs |grep "\"fee-base\":"
   "fee-base": 0,