chore: remove unused dep

Author: DJTB

package.json

@@ -27,7 +27,6 @@
     "babel-eslint": "^8.0.1",
     "babel-plugin-add-module-exports": "^0.2.1",
     "babel-preset-env": "^1.6.0",
-    "babel-preset-flow": "^6.23.0",
     "commitizen": "^2.9.6",
     "cz-conventional-changelog": "^2.0.0",
     "eslint": "^4.8.0",