Fix flaky tests

### How do you use Sentry?

Sentry Saas (sentry.io)

### Version

all

### Steps to Reproduce

No reproduction, but Gentoo has a list of tests they disable to consistently built our package: 
https://github.com/gentoo/gentoo/blob/997938b5b7bf5deb7943b44a2dc52485d14f8076/dev-python/sentry-sdk/sentry-sdk-2.7.1.ebuild#L117-L122

### Expected Result

No flaky tests anymore!

### Actual Result

-