submodule: bump openthread from `f27a3c7` to `e66b9a3` (#67)
submodule: bump openthread from `f27a3c7` to `e66b9a3` (#67)

Bumps [openthread](https://github.com/openthread/openthread) from `f27a3c7` to `e66b9a3`.
- [Commits](https://github.com/openthread/openthread/compare/f27a3c7b2a1a3ab413a0bc89369b7bbcb3f9a1de...e66b9a3958bfdc3fb495a189737265561e9a99bd)

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

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
openthread/ot-samr21,openthread/ot-samr21