v2.2.0

What's Changed

• Start new development phase 2.1.1 by @mmsmits in #282
• Validate CodeableReference with just a reference by @ewoutkramer in #287
• Dependabot: ignore patch updates for test frameworks by @mmsmits in #285
• Bump Microsoft.NET.Test.Sdk from 17.8.0 to 17.9.0 by @dependabot in #288
• Bump xunit from 2.6.6 to 2.7.0 by @dependabot in #290
• Add string validator to report empty strings by @mmsmits in #291
• Bump coverlet.collector from 6.0.0 to 6.0.1 by @dependabot in #292
• Bump coverlet.collector from 6.0.1 to 6.0.2 by @dependabot in #296

Full Changelog: v2.1.0...v2.2.0