Upgrade: Updates prop-types to version 15.7.2

Author: markusguenther

package.json

@@ -26,7 +26,7 @@
   "dependencies": {
     "hoist-non-react-statics": "^3.3.0",
     "invariant": "^2.2.4",
-    "prop-types": "^15.6.2"
+    "prop-types": "^15.7.2"
   },
   "devDependencies": {
     "@babel/cli": "^7.6.4",