Ensure that Allowable Encumbrance and Allowable Expenditure restrictions are based on "Total Funding"

Purpose/Overview:
Ensure that Allowable Encumbrance and Allowable Expenditure restrictions are based on "Total Funding" NOT Allocation

Approach:
Update current calculation logic to check enough money to proceed

org.folio.helper.FinanceHelper#getBudgetRemainingAmountForEncumbrance
[remaining amount we can encumber] = (totalFunding * allowableEncumbered) - unavailable

Acceptance criteria:
Logic updated
Unit tests added
API tests added