[SUGGESTION] Upgrade Framework dependencies

[JKamsker]

This issue is just for keeping track of why we should upgrade the dependencies of the project from net4.5;netstandard1.3;netstandard2.0 to newer versions.

• Microsoft officially doesnt support part of the frameworks anymore
• Span support, tho it can be fixed using the System.Memory package

Open Questions:

• Do polyfills affect newer versions that have the required apis already implemented? (will the polyfill be present in those cases?)

And ofcourse, we would to bump atleast a minor version for that.

Related:

• #2508