Lower minimum auto-liquidity

[Sjors]

I'd like to experiment with giving bots their own phoenixd wallet, but the minimum auto-liquidity of 2 million sats adds quite a high overhead (~22k sats even with extremely low on chain fees).

$ bin/phoenixd --help
Usage: phoenixd [<options>]

Liquidity Options:
  --auto-liquidity=(off|2m|5m|10m)

bin/phoenix-cli estimateliquidityfees --amountSat 2000000
{
    "miningFeeSat": 411,
    "serviceFeeSat": 21000
}

It would be nice the minimum can be lowered to e.g. 100k sats.

Bonus points if phoenix-cli can adjust it (e.g. based on mempool weather).