"Paid after expiration" does not pass "BTCPay_btcPaid" meta data

[astupidmoose]

When an invoice is paid late, BTCPay is not passing the amount paid and this leaves the "BTCPay_btcPaid" meta data blank.

This should be updated with the new amount paid.

[pavlenex]

I agree this is needed. I'm able to replicate it as well.
When (paidLate) BTCPay_btcPaid=0.00000000 which makes accounting harder. For example, for (paidPartial) it works normally.

This together with manually setting invoices #21 are things we need for more accurate accounting.