fix(package): update remark to version 8.0.0

Author: greenkeeper[bot]

package.json

@@ -40,7 +40,7 @@
     "parse-filepath": "^1.0.1",
     "pify": "^3.0.0",
     "read-pkg-up": "^2.0.0",
-    "remark": "^7.0.0",
+    "remark": "^8.0.0",
     "remark-html": "6.0.1",
     "remark-toc": "^4.0.0",
     "remote-origin-url": "0.4.0",