chore(deps): update rust crate sentry-core to 0.31.5

[poliorcetics]

Checklist

• I have read the Contributor Guide
• I have read and agree to the Code of Conduct
• I have added a description of my changes and why I'd like them included in the section below

Description of Changes

Update sentry-core to 0.31 releases

Related Issues

None

[MarijnS95]

>=0.29 already allows 0.31 and up. This was a conscious choice because the updates were coming in too hot, and are typically code-compatible.

Instead an upper bound should be added and released if it turns out to be incompatible with a newer version, and a new version should be released with the lower bound restarting at the new version together with the necessary breaking changes.

As it stands this PR adds nothing besides unnecessarily disallowing users from using sentry-contrib-rust with older versions of sentry-core.

[Jake-Shadle]

Like @MarijnS95 said, this change doesn't meaningfully change anything other than unnecessarily stopping people from using (compatible) older versions of sentry-core.