[REF] Replace deprecated function call with a more readable alternative

[eileenmcnaughton]

Overview

This adds a wrapper to getting financial accounts with the type & uses it rather than the non-deprecated function

Before

Deprecated function called

After

More readable function called

Technical Details

@monishdeb I'd like to advocate for functions like this for getting the financial accounts. They are a pretty thin wrapper on getFinancialAccountForFinancialTypeByRelationship but I feel it's more readable & less error prone (no need to get 'Sales Account Is' exactly right, instead use IDE autocomplete)

Comments

[civibot]

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[eileenmcnaughton]

test this please