Issue Description:-
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When a Sales invoice is fully settled with a Credit note + Payment, Remainder balance appears on the original invoice

Repro Steps:-
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Create a new customer
Create a new SO against above customer, Invoice the SO. Value is 1200
Make a payment journal for 1000 (don’t use settlement option)
Create credit note for 200 against the above SO
Settle all the 3 transactions.
Print the SO invoice created in step 2, we can see balance 200 mentioned in Remainder section, however it should be zero. System is ignoring the Credit note transaction.

Expected Output:-
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After settlement, remainder amount on the invoice should be 0.0.