Bump submodules/cxplat from eec6b42 to cb6e929 (#776)

Bumps [submodules/cxplat](https://github.com/microsoft/cxplat) from `eec6b42` to `cb6e929`.
- [Commits](microsoft/cxplat@eec6b42...cb6e929)

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

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