Symfony 6 & PHP 8.1 support

Hi OAuth2'ers!

This release adds support for Symfony 6 & PHP 8.1. It also drops support for PHP 7.1 and league/oauth2-client 1.x. Details:

v2.9.0

Nov 21st, 2021

Feature

• #341 - Enhancing test matrix, Symfony 6 support, dropping PHP 7.1, client 1.0 - @weaverryan
• #330 - add symfony 6 return types - @jrushlow
• #335 - Removed some deprecations introduced in Symfony 5.x - @DonCallisto
• #310 - Adding FusionAuth provider - @mooreds

Bug Fix

• #309 - Update TwitchClient configuration - @chypriote

Cheers!