build(deps): bump bedrock2 from a75bcca to b39aa28

Bumps [bedrock2](https://github.com/mit-plv/bedrock2) from `a75bcca` to `b39aa28`.
- [Release notes](https://github.com/mit-plv/bedrock2/releases)
- [Commits](mit-plv/bedrock2@a75bcca...b39aa28)

---
updated-dependencies:
- dependency-name: bedrock2
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>