[react-native-windows] English month names on Polish Windows

[drnow4u]

Bug report

Summary

The application with DateTimePicker is running on Polish Windows 10. The name of selected month is in English instead of Polish language.

Reproducible sample code

import React, {type PropsWithChildren, useState} from 'react';
import {
  SafeAreaView,
  ScrollView,
  StatusBar,
  StyleSheet,
  Text,
  useColorScheme,
  View,
} from 'react-native';

import {
  Colors,
  DebugInstructions,
  ReloadInstructions,
} from 'react-native/Libraries/NewAppScreen';
import { Picker } from '@react-native-picker/picker';
import DateTimePicker from "@react-native-community/datetimepicker"


const App = () => {
  const [date, setDate] = useState(new Date());

  return (
    <SafeAreaView>
      <ScrollView
        contentInsetAdjustmentBehavior="automatic">
                <View style={{flex: 2}}>
                  <DateTimePicker
                      locale={"pl-PL"}
                      testID="dateTimePicker1"
                      value={date}
                      mode="date"
                      is24Hour={true}
                      display="default"
                      dateFormat="day month year"
                      onChange={(event, d) => setDate(d)}
                  />
                </View>
      </ScrollView>
    </SafeAreaView>
  );
};

export default App;

Steps to reproduce

1. Run above sample code on MS Windows 10 with Polish language set.

Describe what you expected to happen:

1. The name of the month is presented in Polish language when DateTimePicker is closed
2. The name of the month is presented in Polish language when DateTimePicker is clicked by user to pick date.

Environment info

npx react-native info output:

System:
    OS: Windows 10 10.0.19043
    CPU: (24) x64 Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz
    Memory: 36.35 GB / 63.96 GB
  Binaries:
    Node: 14.17.5 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.22.5 - C:\Program Files (x86)\Yarn\bin\yarn.CMD
    npm: 6.14.14 - C:\Program Files\nodejs\npm.CMD
    Watchman: Not Found
  SDKs:
    Android SDK: Not Found
    Windows SDK:
      AllowDevelopmentWithoutDevLicense: Enabled
      AllowAllTrustedApps: Enabled
      Versions: 10.0.18362.0, 10.0.19041.0
  IDEs:
    Android Studio: Version     2020.3.0.0 AI-203.7717.56.2031.7621141
    Visual Studio: 16.11.32228.343 (Visual Studio Community 2019)
  Languages:
    Java: 1.8.0_171 - C:\Program Files\Java\jdk1.8.0_171\bin\javac.EXE
  npmPackages:
    @react-native-community/cli: Not Found
    react: 18.0.0 => 18.0.0
    react-native: 0.69.5 => 0.69.5
    react-native-windows: 0.69.6 => 0.69.6
  npmGlobalPackages:
    *react-native*: Not Found

datetimepicker version: 6.3.2

Windows version: 10 10.0.19043