chore(package): update lockfile

https://npm.im/greenkeeper-lockfile

Author: greenkeeperio-bot

yarn.lock

@@ -4864,9 +4864,9 @@ [email protected]:
   dependencies:
     prop-types "^15.5.10"
 
-[email protected].0:
-  version "0.20.0"
-  resolved "https://registry.yarnpkg.com/react-native-maps/-/react-native-maps-0.20.0.tgz#52ce428ecc47ddc54faee03cd2a8dc4813b00f91"
+[email protected].1:
+  version "0.20.1"
+  resolved "https://registry.yarnpkg.com/react-native-maps/-/react-native-maps-0.20.1.tgz#b5247a9a26446b2e1ffc3f680db8ba6ccc960096"
   dependencies:
     babel-plugin-module-resolver "^2.3.0"
     babel-preset-react-native "1.9.0"