build(deps): bump xml2js, gatsby-plugin-sharp, gatsby-remark-images and gatsby-transformer-sharp

Removes [xml2js](https://github.com/Leonidas-from-XIV/node-xml2js). It's no longer used after updating ancestor dependencies [xml2js](https://github.com/Leonidas-from-XIV/node-xml2js), [gatsby-plugin-sharp](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-sharp), [gatsby-remark-images](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-remark-images) and [gatsby-transformer-sharp](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-transformer-sharp). These dependencies need to be updated together.


Removes `xml2js`

Updates `gatsby-plugin-sharp` from 2.9.0 to 5.10.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-plugin-sharp/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-plugin-sharp)

Updates `gatsby-remark-images` from 3.6.0 to 7.10.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-remark-images/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-remark-images)

Updates `gatsby-transformer-sharp` from 2.7.0 to 5.10.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-transformer-sharp/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-transformer-sharp)

---
updated-dependencies:
- dependency-name: xml2js
  dependency-type: indirect
- dependency-name: gatsby-plugin-sharp
  dependency-type: direct:production
- dependency-name: gatsby-remark-images
  dependency-type: direct:production
- dependency-name: gatsby-transformer-sharp
  dependency-type: direct:production
...

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

Author: dependabot[bot]