Retrieve invoice by number returns incorrect balance for written off invoice

[reshmabidikar]

Steps to reproduce:

1. Create a new account
2. Create an external charge of $100
3. Write off the invoice
4. Retrieve the invoice by number - This returns the invoice balance as $100. Expected Behavior: The invoice balance should be $0 since the invoice is written off.
5. If the Retrieve Invoice by Id endpoint is used at step 4, it correctly returns the invoice balance as $0.

[reshmabidikar]

Based on some initial investigations, I found the following:

• In DefaultInvoiceDao.getByNumber, invoiceDaoHelper.populateChildren does not set the iswrittenOff flag on the invoice
• This is because getInvoiceTags returns an empty list.
• This is because InternalTenantContext is created without accountRecordId before being passed to the dao.