Assign totalTaxAmount more consistently

[eileenmcnaughton]

Overview

Assign totalTaxAmount more consistently

[civibot]

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[eileenmcnaughton]

@colemanw @seamuslee001 @demeritcowboy should be an easy merge

[eileenmcnaughton]

I think totalTaxAmount would always be set to zero so the ($totalTaxAmount ?? NULL) is proably redundant actually (since it would only kick in if it actually were null

[colemanw]

@eileenmcnaughton can you explain why in the diff it originally called

Civi::settings()->get('contribution_invoice_settings')

But now it calls

Civi::settings()->get('invoicing')

What's the difference?

[eileenmcnaughton]

@colemanw contribution_invoice_settings was a REALLY dumb idea. They created a setting that was an array of settings that had no metadata. Quite a long time ago we separated into separate settings but there is still a wrapper to allow access of the no-longer-existing setting. Once we no longer refer to it in core we can deprecate that wrapper