build(deps): bump loader-utils, gatsby, gatsby-plugin-react-helmet and gatsby-plugin-sass

Bumps [loader-utils](https://github.com/webpack/loader-utils) to 2.0.4 and updates ancestor dependencies [loader-utils](https://github.com/webpack/loader-utils), [gatsby](https://github.com/gatsbyjs/gatsby), [gatsby-plugin-react-helmet](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-react-helmet) and [gatsby-plugin-sass](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-sass). These dependencies need to be updated together.


Updates `loader-utils` from 1.2.3 to 2.0.4
- [Release notes](https://github.com/webpack/loader-utils/releases)
- [Changelog](https://github.com/webpack/loader-utils/blob/v2.0.4/CHANGELOG.md)
- [Commits](webpack/loader-utils@v1.2.3...v2.0.4)

Updates `gatsby` from 3.14.6 to 5.7.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/compare/[email protected]@5.7.0)

Updates `gatsby-plugin-react-helmet` from 4.14.0 to 6.7.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-plugin-react-helmet/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-plugin-react-helmet)

Updates `gatsby-plugin-sass` from 4.14.0 to 6.7.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-plugin-sass/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-plugin-sass)

---
updated-dependencies:
- dependency-name: loader-utils
  dependency-type: indirect
- dependency-name: gatsby
  dependency-type: direct:production
- dependency-name: gatsby-plugin-react-helmet
  dependency-type: direct:production
- dependency-name: gatsby-plugin-sass
  dependency-type: direct:production
...

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

Author: dependabot[bot]