Revert "chainntnfs/btcdnotify: disable height hint cache in testing"
Revert "chainntnfs/btcdnotify: disable height hint cache in testing"

This reverts commit 98e7c968d4bf5900a5d7be7f557eab8f623633c0.

aakselrod/lnd,LightningNetwork/lnd,aakselrod/lnd,LightningNetwork/lnd