build(deps): bump gatsby-remark-autolink-headers from 5.13.0 to 5.15.1 in /docs (#2897)

build(deps): bump gatsby-remark-autolink-headers in /docs

Bumps [gatsby-remark-autolink-headers](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-remark-autolink-headers) from 5.13.0 to 5.15.1.
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/gatsby-remark-autolink-headers@5.15.1/packages/gatsby-remark-autolink-headers/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/gatsby-remark-autolink-headers@5.15.1/packages/gatsby-remark-autolink-headers)

---
updated-dependencies:
- dependency-name: gatsby-remark-autolink-headers
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

docs/package-lock.json

@@ -26,7 +26,7 @@
     "gatsby-plugin-robots-txt": "^1.7.1",
     "gatsby-plugin-sharp": "^4.13.0",
     "gatsby-plugin-sitemap": "^5.13.0",
-    "gatsby-remark-autolink-headers": "^5.13.0",
+    "gatsby-remark-autolink-headers": "^5.15.1",
     "gatsby-remark-copy-linked-files": "^5.13.0",
     "gatsby-remark-external-links": "^0.0.4",
     "gatsby-remark-images": "^6.13.0",