deps: bump gatsby-plugin-styled-components from 6.12.0 to 6.13.0 (#884)

Bumps [gatsby-plugin-styled-components](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-styled-components) from 6.12.0 to 6.13.0. - [Release notes](https://github.com/gatsbyjs/gatsby/releases) - [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-plugin-styled-components/CHANGELOG.md) - [Commits](https://github.com/gatsbyjs/gatsby/commits/gatsby-plugin-styled-components@6.13.0/packages/gatsby-plugin-styled-components) --- updated-dependencies: - dependency-name: gatsby-plugin-styled-components dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>