Bump dropshot from f4b8430 to ab0194f (#946)

Bumps [dropshot](https://github.com/oxidecomputer/dropshot) from `f4b8430` to `ab0194f`.
- [Commits](oxidecomputer/dropshot@f4b8430...ab0194f)

---
updated-dependencies:
- dependency-name: dropshot
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>