[bug][invalid_file_extension] Set file extension filter when picking a document.

[darkstarx]

When picking the file with filter by extension, it allow to choose any file regardless of the extension. And when you pick the file with unsupported extension, flutter_file_dialog just crashes with platform exception.

Code

        final params = OpenFileDialogParams(
          dialogType: OpenFileDialogType.document,
          sourceType: SourceType.photoLibrary,
          fileExtensionsFilter: [ 'pdf', 'doc', 'docx' ],
        );
        final filePath = await FlutterFileDialog.pickFile(params: params);

Exception

2022-10-01 17:49:39 +0000 [SwiftFlutterFileDialogPlugin.swift:24 handle(_:result:)] pickFile
2022-10-01 17:49:39 +0000 [OpenFileDialog.swift:20 deinit] OpenFileDialog.deinit
[DocumentManager] Failed to associate thumbnails for picked URL file:///private/var/mobile/Library/Mobile%20Documents/com~apple~CloudDocs/Desktop/%D0%A1%D0%BD%D0%B8%D0%BC%D0%BE%D0%BA%20%D1%8D%D0%BA%D1%80%D0%B0%D0%BD%D0%B0%202022-09-29%20%D0%B2%2010.48.01.png with the Inbox copy file:///private/var/mobile/Containers/Data/Application/C87255ED-FC01-484D-B95F-AF1BB05FE151/tmp/com.schtandart.online-Inbox/%D0%A1%D0%BD%D0%B8%D0%BC%D0%BE%D0%BA%20%D1%8D%D0%BA%D1%80%D0%B0%D0%BD%D0%B0%202022-09-29%20%D0%B2%2010.48.01.png: Error Domain=QLThumbnailErrorDomain Code=115 "(null)" UserInfo={NSErrorFailingURLKey=file:///private/var/mobile/Library/Mobile%20Documents/com~apple~CloudDocs/Desktop/%D0%A1%D0%BD%D0%B8%D0%BC%D0%BE%D0%BA%20%D1%8D%D0%BA%D1%80%D0%B0%D0%BD%D0%B0%202022-09-29%20%D0%B2%2010.48.01.png}
2022-10-01 17:49:44 +0000 [OpenFileDialog.swift:140 documentPicker(_:didPickDocumentsAt:)] didPickDocumentsAt
2022-10-01 17:49:44 +0000 [OpenFileDialog.swift:154 handlePickedFile(_:)] handlePickedFile: /private/var/mobile/Containers/Data/Application/C87255ED-FC01-484D-B95F-AF1BB05FE151/tmp/com.schtandart.online-Inbox/Снимок экрана 2022-09-29 в 10.48.01.png
[VERBOSE-2:dart_vm_initializer.cc(41)] Unhandled Exception: PlatformException(invalid_file_extension, Invalid file type was picked, png, null)
#0      StandardMethodCodec.decodeEnvelope
package:flutter/…/services/message_codecs.dart:653
#1      MethodChannel._invokeMethod
package:flutter/…/services/platform_channel.dart:296
<asynchronous suspension>
#2      _MediaFieldState._takePicture
package:schtd_dealer/…/common/media_field.dart:299

Platform: iOS Flutter 3.3.3