devel/py-strawberry-graphql: Update to 0.312.4

Changelog since 0.312.2:

https://github.com/strawberry-graphql/strawberry/blob/0.312.4/CHANGELOG.md

MFH: 2026Q2
Security: 6a0aa20d-399f-11f1-8626-901b0edee044
(cherry picked from commit 0997d1261ec995b8dc16557e1d82fe4f67f65773)