Fix windows abi3 builds
It looks like setuptools-rust doesn't support abi3 builds targetting python 3.7 any more.
Since 3.7 is end of life anyway, I've bumped all the builds to target 3.8 instead.
Edited by Benjamin Winger
The 17.0 major release is coming on May 16, 2024! This version brings many exciting improvements to GitLab, but also removes some deprecated features. We are introducing three breaking change windows during which we expect breaking changes to be deployed to GitLab.com. You can read more about it on our blogpost. The second breaking change window begins 2024-04-29 09:00 UTC and ends 2024-05-01 22:00 UTC.
It looks like setuptools-rust doesn't support abi3 builds targetting python 3.7 any more.
Since 3.7 is end of life anyway, I've bumped all the builds to target 3.8 instead.