Major update to PS7, Sampler, Azure Pipelines, Pester 5 and more.

[raandree]

This pull request removes several PowerShell build and test helper scripts from the repository. These scripts covered build orchestration, environment setup, cleaning build outputs, running and reporting tests, deploying with PSDeploy, and updating DSC resource schemas. Their removal suggests a significant change in how builds and tests are managed, potentially moving to a new build system or approach.

• This fixes Migrate to sampler #4.
• This fixes Fixed Typo at Unprotect-Datum.ps1 #6.

The most important changes are:

Build Orchestration and Helpers:

• Removed the main build orchestration script .build.ps1, which coordinated task execution, dependency resolution, environment setup, and build pipelines.
• Deleted helper scripts for cleaning build outputs (.build/BuildHelpers/Clean.BuildHelpers.build.ps1) and setting environment variables (.build/BuildHelpers/Environment.BuildHelpers.build.ps1). [1] [2]

Testing Pipeline:

• Removed scripts for running Pester unit tests, integration tests, and quality tests, as well as enforcing code coverage and test result assertions (.build/Pester/UnitTests.pester.build.ps1, .build/Pester/IntegrationTests.pester.build.ps1, .build/Pester/QualityTests.pester.build.ps1). [1] [2] [3]
• Deleted the script for uploading test results to AppVeyor (.build/Appveyor/TestResultUpload.Appveyor.build.ps1).

Deployment and DSC Resource Management:

• Removed the deployment script using PSDeploy (.build/PSDeploy/DeployAll.PSDeploy.build.ps1).
• Deleted scripts for updating DSC resource schemas from definitions (.build/Dsc/UpdateDscResourceFromDefinition.ps1, .build/Dsc/UpdateDscResourceFromDefinition.build.ps1). [1] [2]

[raandree]

We need a pipeline on Azure, AppVeyor is not longer working.