chore(deps): bump the gatsby group across 1 directory with 6 updates (#1183)

Bumps the gatsby group with 6 updates in the / directory:

| Package | From | To |
| --- | --- | --- |
| [gatsby](https://github.com/gatsbyjs/gatsby) | `5.14.6` | `5.15.0` |
| [gatsby-plugin-google-analytics](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-google-analytics) | `5.14.0` | `5.15.0` |
| [gatsby-plugin-sass](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-sass) | `6.14.0` | `6.15.0` |
| [gatsby-remark-autolink-headers](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-remark-autolink-headers) | `6.14.0` | `6.15.0` |
| [gatsby-source-filesystem](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-source-filesystem) | `5.14.0` | `5.15.0` |
| [gatsby-transformer-remark](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-transformer-remark) | `6.14.0` | `6.15.0` |



Updates `gatsby` from 5.14.6 to 5.15.0
- [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]@5.15.0)

Updates `gatsby-plugin-google-analytics` from 5.14.0 to 5.15.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-plugin-google-analytics/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-plugin-google-analytics)

Updates `gatsby-plugin-sass` from 6.14.0 to 6.15.0
- [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)

Updates `gatsby-remark-autolink-headers` from 6.14.0 to 6.15.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-remark-autolink-headers/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-remark-autolink-headers)

Updates `gatsby-source-filesystem` from 5.14.0 to 5.15.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-source-filesystem/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-source-filesystem)

Updates `gatsby-transformer-remark` from 6.14.0 to 6.15.0
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-transformer-remark/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-transformer-remark)

---
updated-dependencies:
- dependency-name: gatsby
  dependency-version: 5.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: gatsby
- dependency-name: gatsby-plugin-google-analytics
  dependency-version: 5.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: gatsby
- dependency-name: gatsby-plugin-sass
  dependency-version: 6.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: gatsby
- dependency-name: gatsby-remark-autolink-headers
  dependency-version: 6.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: gatsby
- dependency-name: gatsby-source-filesystem
  dependency-version: 5.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: gatsby
- dependency-name: gatsby-transformer-remark
  dependency-version: 6.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: gatsby
...

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

Author: dependabot[bot]

package.json

@@ -18,16 +18,16 @@
     "@docsearch/react": "3",
     "@reach/router": "^1.3.4",
     "classnames": "^2.2.6",
-    "gatsby": "^5.14.6",
+    "gatsby": "^5.15.0",
     "gatsby-plugin-env-variables": "^2.3.0",
-    "gatsby-plugin-google-analytics": "^5.14.0",
+    "gatsby-plugin-google-analytics": "^5.15.0",
     "gatsby-plugin-netlify": "^5.1.1",
     "gatsby-plugin-react-helmet": "6.15.0",
-    "gatsby-plugin-sass": "6.14.0",
-    "gatsby-remark-autolink-headers": "6.14.0",
+    "gatsby-plugin-sass": "6.15.0",
+    "gatsby-remark-autolink-headers": "6.15.0",
     "gatsby-remark-mermaid": "^5.0.0",
-    "gatsby-source-filesystem": "^5.14.0",
-    "gatsby-transformer-remark": "6.14.0",
+    "gatsby-source-filesystem": "^5.15.0",
+    "gatsby-transformer-remark": "6.15.0",
     "json2yaml": "^1.1.0",
     "lodash": "^4.17.19",
     "monaco-editor": "^0.52.0",