Addition of comment explaining use of ansible over vagrant powershell

ansible/pbTestScripts/testScript.sh

@@ -149,7 +149,7 @@ testBuildWin()
 	# Ensures the git config won't change line endings
 	vagrant powershell -c "Start-Process powershell -Verb runAs; C:/cygwin64/bin/sed -i -e 's/autocrlf.*/autocrlf = false/g' C:\\ProgramData/Git/config"
 	vagrant powershell -c "cd C:/; if (-not (Test-Path C:/openjdk-build -PathType Container) ) { echo 'Cloning openJDK-build repo' ; git clone https://github.com/adoptopenjdk/openjdk-build ; sleep 3 }"
-	# Runs the build script via ansible
+	# Runs the build script via ansible, as vagrant powershell gives error messages that ansible doesn't. See: https://github.com/AdoptOpenJDK/openjdk-infrastructure/pull/942#issuecomment-539946564
 	cd $WORKSPACE/adoptopenjdkPBTests/$folderName-$branchName/ansible && ansible all -i playbooks/AdoptOpenJDK_Windows_Playbook/hosts.win -u vagrant -m raw -a "Start-Process powershell.exe -Verb runAs; cd C:/; sh C:/vagrant/pbTestScripts/buildJDKWin.sh"
 }