Example powershell script needed for Gitlab Multi Runner

Since the old Gitlab Multi Runners will not work after September 22, 2017 we tried to update from from version 1.3.4 to 9.5.0. We did notice that no matter what we do we cannot get the runner to run using the bash shell. We have created a ticket at Gitlab about this. https://gitlab.com/gitlab-org/gitlab-runner/issues/2759

Does anyone have an example of a yaml script using Powershell to do the Exec rather than bash?