Bump Verify.NUnit from 30.13.0 to 30.15.0#667

dependabot[bot] wants to merge 1 commit intomainVerifyTests/Verify.ImageSharp:mainfrom

dependabot/nuget/src/Verify.NUnit-30.15.0VerifyTests/Verify.ImageSharp:dependabot/nuget/src/Verify.NUnit-30.15.0Copy head branch name to clipboard