undefind is not an object (" thi

参考：https://github.com/react-navigation/react-navigation/issues/5854#issuecomment-493775447

解决方法：

package.json添加：

"@babel/plugin-transform-flow-strip-types": "^7.16.2",
    "@babel/plugin-proposal-class-properties": "^7.16.7",
    "@babel/plugin-proposal-decorators": "^7.17.9",