Fix outstanding balance sum in payment report

Update all locales with the latest Transifex translations

Defend against nils in variant serializer

If unit_price.denominator ever returns nil, the serializer won't explode now.

Merge pull request openfoodfoundation#7222 from openfoodfoundation/tr…

…ansifex

Transifex

Update from Transifex

Merge pull request openfoodfoundation#7086 from Matt-Yorkley/adjustme…

…nts-index

[Adjustments] Add index on spree_adjustments.order_id

Add index on spree_adjustments.order_id

Merge pull request openfoodfoundation#7036 from Matt-Yorkley/adjustme…

…nts-callbacks

[Adjustments] Reduce adjustments callbacks

Update all locales with the latest Transifex translations

Update all locales with the latest Transifex translations