lnwallet: add test to ensure that all backends show unconf txns in ListTransactionDetails
lnwallet: add test to ensure that all backends show unconf txns in ListTransactionDetails

In this commit, we add a new test to the set of lnwallet integration
tests. In this new test, we aim to ensure that all backends are able to
display unconfirmed transactions in ListChainTransactions. As of this
commit, this test fails as no backends will return unconfirmed
transactions properly.

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