Fix misleading error when .NET runtime files missing during agent configuration#5371

Copilot wants to merge 3 commits intomastermicrosoft/azure-pipelines-agent:masterfrom

copilot/fix-6154722-53052789-8cf6c7c3-0001-4aed-99ae-b48db3b0e7d4microsoft/azure-pipelines-agent:copilot/fix-6154722-53052789-8cf6c7c3-0001-4aed-99ae-b48db3b0e7d4Copy head branch name to clipboard