Bump gutenberg from 7fcc61e to 39b57b0

Bumps [gutenberg](https://github.com/WordPress/gutenberg) from `7fcc61e` to `39b57b0`.
- [Release notes](https://github.com/WordPress/gutenberg/releases)
- [Commits](WordPress/gutenberg@7fcc61e...39b57b0)

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

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