set method Null safety
Uploads a custom video thumbnail to YouTube and sets it for a video.
Implementation
Future<ThumbnailSetResponse> set(
{required String videoId,
required String uploadId,
required File thumbnail}) async {
String uploadType = 'resumable';
return await _rest.set(_authHeader, 'application/x-www-form-urlencoded',
videoId, uploadId, thumbnail, uploadType);
}