Need to do proper accounting in LenderGroup contract when accepting funds from Escrow

[ethereumdegen]

   function withdrawFromEscrowVault ( uint256 _amount ) public whenForwarderNotPaused whenNotPaused {

        address _escrowVault = ITellerV2(TELLER_V2).getEscrowVault();

        IEscrowVault(_escrowVault).withdraw(address(principalToken), _amount );

    }

Need to increment accounting for amount repaid..

[ethereumdegen]

fixed in #62