Bump submodules/vipr from ce3bd30 to d6af76a

Bumps [submodules/vipr](https://github.com/microsoft/vipr) from `ce3bd30` to `d6af76a`.
- [Release notes](https://github.com/microsoft/vipr/releases)
- [Commits](microsoft/Vipr@ce3bd30...d6af76a)

---
updated-dependencies:
- dependency-name: submodules/vipr
  dependency-type: direct:production
...

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

Author: dependabot[bot]