Breaking Changes

• Removed netcoreapp3.1 support/testing (#1401).
• Converted ResolveRequest into a readonly struct (#1397 - thanks @SergeiPavlov!).

Additional Changes

• Added net8.0 target (#1401).
• Replaced use of Moq in tests with NSubstitute (#1390 - thanks @aydjay!).

Full Changelog: v7.1.0...v8.0.0