chore(deps): bump cross-spawn and gatsby-cli in /site

Bumps [cross-spawn](https://github.com/moxystudio/node-cross-spawn) and [gatsby-cli](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-cli). These dependencies needed to be updated together.

Updates `cross-spawn` from 7.0.3 to 7.0.5
- [Changelog](https://github.com/moxystudio/node-cross-spawn/blob/master/CHANGELOG.md)
- [Commits](moxystudio/node-cross-spawn@v7.0.3...v7.0.5)

Updates `gatsby-cli` from 5.12.4 to 5.14.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-cli/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-cli)

---
updated-dependencies:
- dependency-name: cross-spawn
  dependency-type: indirect
- dependency-name: gatsby-cli
  dependency-type: indirect
...

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