Bug 31513: Remove price formatting form data- attributes

Bug 31513: Remove price formatting form data- attributes

We cannot use data formatted with a decimal comma for
calculations. So we need to make sure that the data- attributes
passed to the modals are in 'database format' with decimal .

This will fix the NaN errors on the forms, but might also
negatively effect formatting in some spots.
Formatting should be fixed separately as this is for sure the
right first step, but we need to put in more work for displays.

To test:
* Set CurrencyFormat system preference to FR
* Go to any patron account > accounting tab
* Create a credit
* On Transactions tab: Payout amount at bottom = Verify NaN in input
* On Transactions tab: Issue payout on the credit line = Verify NaN in input
* Create a manual debit and pay it
* On Transactions tab: Issue refund = Verify NaN in input
* Apply patch
* Repeat test plan
* Now all input fields should be set with the correct amounts

https://bugs.koha-community.org/show_bug.cgi?id=31486

Signed-off-by: Michaela Sieber <michaela.sieber@kit.edu>
Signed-off-by: Joonas Kylmälä <joonas.kylmala@iki.fi>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>