Update rollup-plugin-filesize to the latest version 🚀 (#81)

* chore(package): update rollup-plugin-filesize to version 7.0.0

* chore(package): update lockfile package-lock.json

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

Author: greenkeeper[bot]

package-lock.json

@@ -92,7 +92,7 @@
     "react-test-renderer": "^16.13.0",
     "rollup": "^2.0.0",
     "rollup-plugin-babel": "^4.3.3",
-    "rollup-plugin-filesize": "^6.2.1",
+    "rollup-plugin-filesize": "^7.0.0",
     "rollup-plugin-local-resolve": "^1.0.7",
     "rollup-plugin-peer-deps-external": "^2.2.2",
     "rollup-plugin-postcss": "^2.1.1",