Bump marked from 1.1.1 to 2.0.0 (#69)

Bumps [marked](https://github.com/markedjs/marked) from 1.1.1 to 2.0.0.
- [Release notes](https://github.com/markedjs/marked/releases)
- [Changelog](https://github.com/markedjs/marked/blob/master/release.config.js)
- [Commits](markedjs/marked@v1.1.1...v2.0.0)

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

Author: dependabot[bot]

package-lock.json

@@ -23,7 +23,7 @@
     "gatsby-plugin-smoothscroll": "^1.2.0",
     "gatsby-plugin-use-dark-mode": "^1.1.2",
     "gatsby-transformer-sharp": "^2.5.12",
-    "marked": "^1.1.1",
+    "marked": "^2.0.0",
     "prop-types": "^15.7.2",
     "react": "^16.13.1",
     "react-dom": "^16.13.1",