chore(dependencies): Bump rollup from 0.51.5 to 0.51.8

Bumps [rollup](https://github.com/rollup/rollup) from 0.51.5 to 0.51.8.
- [Changelog](https://github.com/rollup/rollup/blob/master/CHANGELOG.md)
- [Commits](rollup/rollup@v0.51.5...v0.51.8)

package.json

@@ -67,7 +67,7 @@
     "nyc": "^11.3.0",
     "remark": "^8.0.0",
     "remark-lint": "^6.0.1",
-    "rollup": "^0.51.5",
+    "rollup": "^0.51.8",
     "rollup-plugin-babel": "^2.7.1",
     "rollup-plugin-commonjs": "^8.2.6"
   },

yarn.lock

@@ -3521,9 +3521,9 @@ rollup-pluginutils@^2.0.1:
     estree-walker "^0.3.0"
     micromatch "^2.3.11"
 
-rollup@^0.51.5:
-  version "0.51.5"
-  resolved "https://registry.yarnpkg.com/rollup/-/rollup-0.51.5.tgz#5caf9101fcaefe344065701ece7de697631a8035"
+rollup@^0.51.8:
+  version "0.51.8"
+  resolved "https://registry.yarnpkg.com/rollup/-/rollup-0.51.8.tgz#58bd0b642885f4770b5f93cc64f14e4233c2236d"
 
 run-async@^2.2.0:
   version "2.3.0"