chore(package): update rollup to version 2.0.0

Co-authored-by: greenkeeper[bot] <23040076+greenkeeper[bot]@users.noreply.github.com>

Author: greenkeeper[bot]

package-lock.json

@@ -60,7 +60,7 @@
     "eslint-plugin-import": "^2.20.1",
     "husky": "^4.2.3",
     "jest": "^25.1.0",
-    "rollup": "^1.31.1",
+    "rollup": "^2.0.0",
     "rollup-plugin-babel": "^4.3.3",
     "rollup-plugin-babel-minify": "^9.1.1",
     "rollup-plugin-filesize": "^6.2.1",