[image_picker_platform_interface] Added pickMultiImage (flutter#3782)

* Added pickMultiImage to image_picker_platform_interface

* Added tests

* fixed platform_interface tests

* Added tests

* fixed platform_interface tests

* Fixed tests

* Fixed version in pubspec.yaml

* Added test for imageQuality value; Implemented feedback

* Format

[google_sign_in] Fix "pick account" on iOS (flutter#3805)

[local_auth] Fix iOS crash when no localizedReason (flutter#3780)

[flutter_webview] Fix `allowsInlineMediaPlayback` ignored on iOS (flu…

…tter#3791)

[in_app_purchase] Configured example app to use StoreKit Testing on i…

…OS 14 (flutter#3772)

[in_app_purchase] improve readme (flutter#3731)

[google_map_flutter] fix version (flutter#3790)

[local_auth] Fix callback thread handling (flutter#3778)

Ensure that all auth replies, which are sent on an internal framework queue per documentation, are dispatched back to the main thread for handling, as all resulting operations (method channel callbacks, display of UI) are things that must be done on the main thread

In order to test this, sets up local_auth with XCTest-based tests, and adds the ability to inject a mock LAContext. (This does not do full unit test backfill, to limit the scope of the PR.)

Fixes flutter/flutter#47465

[local_auth] Update Jetpack dependencies (flutter#3786)

The plugin was still using several beta version of Jetpack libraries
from 2 years ago. Updates to the latest stable version of each.

Fixes flutter/flutter#52742

[video_player]Update README.me (flutter#3713)