test: Fix open handles to improve test lisibility

We have a lot of open handles flooding the end of our test results. It seems that they are due to a React issue fixed in 18+.

Dan Abramov wrote a small package to fix the issue temporarly. I added it here manually because it has an error in the semver version check. This code should be removed when upgrading React to 18+.

facebook/react#20756 (comment)

__tests__/jestSetupFile.js

@@ -1,3 +1,5 @@
+import './openHandleFix'
+
 import mockNotifee from '@notifee/react-native/jest-mock'
 import mockAsyncStorage from '@react-native-async-storage/async-storage/jest/async-storage-mock'
 import mockRNCameraRoll from '@react-native-camera-roll/camera-roll/src/__mocks__/nativeInterface'

__tests__/openHandleFix.js

@@ -0,0 +1,34 @@
+/* eslint-disable no-console */
+/* eslint-disable prettier/prettier */
+'use strict';
+
+// -- Added by Cozy --
+// This code is taken from react-16-node-hanging-test-fix package
+// which has an error in the semver version check
+// -- Added by Cozy --
+
+// See https://github.com/facebook/react/issues/20756
+// This fix is only useful in a test environment with
+// Node 15+, jsdom, and React < 17.1.0.
+
+// It must be imported *before* any imports of 'react-dom'.
+
+const version = require('react').version;
+const semverGt = require('semver/functions/gt');
+
+if (Object.prototype.toString.call(process) !== '[object process]') {
+  throw Error(
+    'The `react-16-node-hanging-test-fix` package must only be used in a Node environment. ' +
+    'Remove this import from your application code.'
+  );
+}
+
+if (semverGt(version, '18.0.0')) {
+  console.error(
+    'The `react-16-node-hanging-test-fix` package is no longer needed ' +
+    'with React ' + version + ' and may cause issues. Remove this import.'
+  )
+}
+
+// This is the "fix".
+delete global.MessageChannel;