PR Summary

This is due to a regression in Azure Pipelines expressions, which used to work the way they were but a few weeks ago they somehow changed their behaviour and now don't pass the parameter any more, meaning that the tests that were supposed to run on Windows PowerShell in the test matrix were actually run on PowerShell Core.
Changing to a run-time expression instead of a runtime expression for the moment to fix this
https://docs.microsoft.com/en-us/azure/devops/pipelines/process/expressions?view=azure-devops#variables

I submitted this bug report: https://developercommunity.visualstudio.com/content/problem/996647/boolean-compile-time-yaml-expression-not-correctly.html

PR Checklist

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