FINERACT-2455: Working Capital - Undo disbursement and discount fix

[somasorosdpc]

Description

• if WC loan product has defined discount value, e.g. 50 and disallow attributes(discount) override setting
  ** Apply
  *** during loan account application default discount is set as proposed discount
  *** after creation loan details has correct proposed discount field value
  ** Approve
  *** approve loan template should contain this value and new value to disable UI field
  *** approval with provided 50 discount or null should result as approve the default 50 for loan
  *** after approval loan details has correct approved discount field value
  ** Disburse
  *** disburse loan template should contain this value and new value to disable UI field
  *** disburse with provided 50 discount or null should result to have discount fee transaction created with the default 50 for loan

Checklist

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[galovics]

LGTM