Bug 11229: makepayment doesn't log branch in statistics correctly

This patch fixes makepayment() so it correctly logs the branch code
to the statistics table.

To test:
- Run (with the regression tests applied)
  $ prove t/db_dependent/Accounts.t
=> FAIL: makepayment() tests fail because logging is wrong
- Apply the patch
- Run
  $ prove t/db_dependent/Accounts.t
=> SUCCESS: tests for makepayment now pass
(Note: makepartialpayment tests still fail as they need the next patch)

Original commit message relying on the UI to test:

There are several ways of paying fines, not all of them
recorded the branch the payment was made at correctly:

1) Pay button next to an individual fine
2) Checkbox + pay amount
3) Checkbox + pay selected

For each of those, check if the payment registered in
the table statistics contains the branchcode before
and after the patch.

The patch should fix 1).
2) and 3) are ok with and without the patch.

Important: Don't change the amount, pay individual fines.

Signed-off-by: Tomas Cohen Arazi <tomascohen@unc.edu.ar>
Note: i fixed the commit message, because this is a fix for makepayment

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@unc.edu.ar>

C4/Accounts.pm

@@ -276,7 +276,7 @@ sub makepayment {
     }
 
     UpdateStats({
-                branch => $user,
+                branch => $branch,
                 type => 'payment',
                 amount => $amount,
                 borrowernumber => $borrowernumber,