fix(package): update react-navigation to version 1.5.12

Author: greenkeeper[bot]

package.json

@@ -130,7 +130,7 @@
     "react-native-tableview-simple": "0.17.5",
     "react-native-typography": "1.3.0",
     "react-native-vector-icons": "4.6.0",
-    "react-navigation": "1.5.11",
+    "react-navigation": "1.5.12",
     "react-redux": "5.0.7",
     "redux": "3.7.2",
     "redux-logger": "3.0.6",