chore(package): update lockfile

https://npm.im/greenkeeper-lockfile

Author: greenkeeperio-bot

yarn.lock

@@ -671,9 +671,9 @@ deep-extend@~0.4.0:
   version "0.4.2"
   resolved "https://registry.yarnpkg.com/deep-extend/-/deep-extend-0.4.2.tgz#48b699c27e334bf89f10892be432f6e4c7d34a7f"
 
-deepmerge@^1.5.0:
-  version "1.5.0"
-  resolved "https://registry.yarnpkg.com/deepmerge/-/deepmerge-1.5.0.tgz#00bc5b88fd23b8130f9f5049071c3420e07a5465"
+deepmerge@2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/deepmerge/-/deepmerge-2.0.0.tgz#35f7ee08e8bde1173b3a529f732dcda67ce82e29"
 
 default-require-extensions@^1.0.0:
   version "1.0.0"