Build(deps): Bump @wordpress/blocks from 15.6.0 to 15.7.0

Bumps [@wordpress/blocks](https://github.com/WordPress/gutenberg/tree/HEAD/packages/blocks) from 15.6.0 to 15.7.0.
- [Release notes](https://github.com/WordPress/gutenberg/releases)
- [Changelog](https://github.com/WordPress/gutenberg/blob/trunk/packages/blocks/CHANGELOG.md)
- [Commits](https://github.com/WordPress/gutenberg/commits/@wordpress/blocks@15.7.0/packages/blocks)

---
updated-dependencies:
- dependency-name: "@wordpress/blocks"
  dependency-version: 15.7.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]