1.4.0

• Add .NET 9.0 support
• Drop .NET 6.0 support
• Drop .NET 7.0 support
• Change API authentication method (https://us.forums.blizzard.com/en/blizzard/t/upcoming-changes-to-battlenet’s-api-gateway/51561)
• Various CI/Tests housekeeping

Full Changelog: 1.3.0...1.4.0