Bug 31038: Fix price formating in cashup summary

Bug 31038: Fix price formating in cashup summary

This patch uses the existing format_price JS include to format prices in
the cashup summary modal

Test plan
1) Create some transactions and a cashup
2) View the cashup summary modal and confirm amounts are not nicely
   formatted
3) Apply patch
4) Confirm amounts in cashup summary modals are now nicely formatted

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit f46b636d03aa6e35c97f8c00cc7d6f0c6f4dbc94)

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>