Bump gatsby-plugin-mdx from 1.2.13 to 2.14.1

Bumps [gatsby-plugin-mdx](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-mdx) from 1.2.13 to 2.14.1.
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/[email protected]/packages/gatsby-plugin-mdx/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/[email protected]/packages/gatsby-plugin-mdx)

---
updated-dependencies:
- dependency-name: gatsby-plugin-mdx
  dependency-type: direct:production
...

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

Author: dependabot[bot]

Diff for: package.json

@@ -38,7 +38,7 @@
     "gatsby-plugin-google-analytics": "^2.0.9",
     "gatsby-plugin-lunr": "^1.5.2",
     "gatsby-plugin-manifest": "2.3.3",
-    "gatsby-plugin-mdx": "^1.2.6",
+    "gatsby-plugin-mdx": "^2.14.1",
     "gatsby-plugin-offline": "^2.2.9",
     "gatsby-plugin-page-creator": "^2.3.8",
     "gatsby-plugin-printer": "1.0.8",