.NET 5 support

[mikoskinen]

Currently API Framework targets the LTS version of .NET Core, meaning .NET Core 3.1. The current idea is to jump from 3.1 to .NET 6 as that is the next LTS but support for .NET 5 is still under consideration.

Please let us know what you think, should .NET 5 be supported?

[gmddmg]

I would better go straight to .net 6

[ryzam]

I vote to support straight to .Net 6