fixed picker import

Author: Simranjit1080

src/basic/PickerItem.js

@@ -1,5 +1,5 @@
 import React, { Component } from 'react';
-import Picker from '@react-native-community/picker';
+import { Picker } from '@react-native-community/picker';
 import { connectStyle } from 'native-base-shoutem-theme';
 
 import mapPropsToStyleNames from '../utils/mapPropsToStyleNames';