Bump @mdx-js/mdx from 0.18.2 to 0.19.0 (#257)

Bumps [@mdx-js/mdx](https://github.com/mdx-js/mdx) from 0.18.2 to 0.19.0.
- [Release notes](https://github.com/mdx-js/mdx/releases)
- [Changelog](https://github.com/mdx-js/mdx/blob/master/changelog.md)
- [Commits](https://github.com/mdx-js/mdx/compare/v0.18.2...v0.19.0)

Signed-off-by: dependabot[bot] <support@dependabot.com>

package-lock.json

@@ -1848,9 +1848,9 @@
       }
     },
     "@mdx-js/mdx": {
-      "version": "0.18.2",
-      "resolved": "https://registry.npmjs.org/@mdx-js/mdx/-/mdx-0.18.2.tgz",
-      "integrity": "sha512-7DqNBOGPV+36qpH8YZmKI5uvuXhrGZFhJ4C9+9uaQSpH2hQg9xAfdzjSSEO8FQhAlu6wJtUgb72J5/eWdc1HFw==",
+      "version": "0.19.0",
+      "resolved": "https://registry.npmjs.org/@mdx-js/mdx/-/mdx-0.19.0.tgz",
+      "integrity": "sha512-RkiTJqAjVdIVxRNH0YATyHUj0P0HD/JgDF7OKCHrt1LcyAScdMSHDk5QAHLGPmfW1f0j+dyAQhkM5wkw8Dr3Nw==",
       "dev": true,
       "requires": {
         "@babel/plugin-proposal-object-rest-spread": "^7.3.2",

package.json

@@ -39,7 +39,7 @@
     "serve-marked": "^0.4.0"
   },
   "devDependencies": {
-    "@mdx-js/mdx": "^0.18.2",
+    "@mdx-js/mdx": "^0.19.0",
     "@zeit/next-mdx": "^1.2.0",
     "babel-eslint": "^10.0.1",
     "micro-dev": "^3.0.0",