itest: extend testAnchorReservedValue to open additional channels
itest: extend testAnchorReservedValue to open additional channels

We do this to trigger a bug that will be resolved in a follow-up commit.
This bug prevents inbound legacy channels from being rejected by the
recipient if they have at least one anchor channel already opened
without an on-chain balance.

aakselrod/lnd,aakselrod/lnd