chore(deps): update System.Reactive requirement from 5.* to 6.* in /src#264

ChrisPulman merged 1 commit intomainreactiveui/punchclock:mainfrom

dependabot/nuget/src/System.Reactive-6.starreactiveui/punchclock:dependabot/nuget/src/System.Reactive-6.starCopy head branch name to clipboard