Unity test tools and SteamVR plugin, suppress "no hmd" error when running tests

I created an empty project in 5.4, imported SteamVR and Unity Test tools. I created a scene added an integration test to it. When I run the test I get the following error:

I do not have Hmd connected, because I am running a test. The test runs, but I get the error messages in the log. What can I do to so that these errors do not show up?

Thanks.