Track HTTP request version

[LucasPickering]

Description

Describe the change. If there is an associated issue, please include the issue link (e.g. "Closes #xxx"). For UI changes, please also include screenshots.

Track HTTP request version in the DB. reqwest uses HTTP/1.1 by default, and we've never allowed customization, so all historical requests will have used that version.

Known Risks

What issues could potentially go wrong with this change? Is it a breaking change? What have you done to mitigate any potential risks?

This is kinda dead code for now because there's no way to customize the version yet, but that's coming next.

QA

How did you test this?

Ran some tests manually, nothing much else to test yet.

Checklist

• Have you read CONTRIBUTING.md already?
• Did you update CHANGELOG.md?
  • Only user-facing changes belong in the changelog. Internal changes such as refactors should only be included if they'll impact users, e.g. via performance improvement.
• Did you remove all TODOs?
  • If there are unresolved issues, please open a follow-on issue and link to it in a comment so future work can be tracked