Resolve "AnonymousUser iteration at /boutique/order/edit"

Closes #51

See merge request !57

`setup` runs before any permission check, so it should not access the
current user object

Fixes #51

Update postgresql to version 13

See merge request !58

: Upgrading to python3.9

See merge request !54

MOREAU Ulysse authored Jan 20, 2021 and VAN ZUIJLEN Nils committed Jan 20, 2021

(this is mostly to check if tests still passes)

Delete illegal products from basket

See merge request !56

Fix edit before payment

See merge request !55

Add email in product csv export

See merge request !53