Bump docs/themes/docsy from 55e0ce2 to 706e23c

Bumps [docs/themes/docsy](https://github.com/google/docsy) from `55e0ce2` to `706e23c`.
- [Release notes](https://github.com/google/docsy/releases)
- [Commits](google/docsy@55e0ce2...706e23c)

---
updated-dependencies:
- dependency-name: docs/themes/docsy
  dependency-type: direct:production
...

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

Author: dependabot[bot]