Adding TestAdapter hardware support

[Ellerbach]

One of the most wanted feature is to have hardware Unit Test working for nanoFramework: this PR is just about that!

Description

Adding TestAdapter hardware support

Motivation and Context

• Add real hardware support in the Unit Test framework

How Has This Been Tested?

tested with an ESP32, both with the simple NFUnitTest template and also the nanoFramework.Json tests.

This will require to adjust the nuget, the target version has been changed for .NET 4.8. And adjust the path in the nuget as well.

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Config and build (change in the configuration and build system, has no impact on code or features)
• Dependencies (update dependencies and changes associated, has no impact on code or features)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[josesimoes]

@Ellerbach you need to remove this BACKUP file... 😁

[josesimoes]

Looks good! just remove that backup csproj and we're good to merge.
(always SQUASH AND MERGE please)

[josesimoes]

@nfbot updatedependencies

[josesimoes]

@nfbot updatedependencies

[josesimoes]

@nfbot updatedependencies

[josesimoes]

@nfbot updatedependencies

[josesimoes]

@nfbot updatedependencies