chore: remove unused babel-core dependency

Author: SimenB

package.json

@@ -47,7 +47,6 @@
     "@babel/core": "^7.0.1",
     "@babel/plugin-transform-modules-commonjs": "^7.0.0",
     "@babel/preset-env": "^7.0.0",
-    "babel-core": "^7.0.0-bridge.0",
     "babel-jest": "^24.0.0",
     "babel-plugin-add-module-exports": "^1.0.0",
     "classnames": "^2.2.5",

yarn.lock

@@ -1056,11 +1056,6 @@ aws4@^1.8.0:
   resolved "https://registry.yarnpkg.com/aws4/-/aws4-1.8.0.tgz#f0e003d9ca9e7f59c7a508945d7b2ef9a04a542f"
   integrity sha512-ReZxvNHIOv88FlT7rxcXIIC0fPt4KZqZbOlivyWtXLt8ESx84zd3kMC6iK5jVeS2qt+g7ftS7ye4fi06X5rtRQ==
 
-babel-core@^7.0.0-bridge.0:
-  version "7.0.0-bridge.0"
-  resolved "https://registry.yarnpkg.com/babel-core/-/babel-core-7.0.0-bridge.0.tgz#95a492ddd90f9b4e9a4a1da14eb335b87b634ece"
-  integrity sha512-poPX9mZH/5CSanm50Q+1toVci6pv5KSRv/5TWCwtzQS5XEwn40BcCrgIeMFWP9CKKIniKXNxoIOnOq4VVlGXhg==
-
 babel-jest@^24.0.0:
   version "24.0.0"
   resolved "https://registry.yarnpkg.com/babel-jest/-/babel-jest-24.0.0.tgz#8a0c767f03f4a595fb921afdab13ff126edd00da"