We need to support running tests in root privilege on Linux Travis CI in a similar way as our windows tests running in AppVeyor. For windows tests, we have a tag RequireAdminOnWindows to indicate the tests that need admin privilege. We run those tests in an admin pwsh session, and then we use runas to remove admin privilege and run the rest tests.
With sudo: required in .travis.yml, Travis CI Linux builds run in regular user privilege by default, but you can get the root privilege using sudo with no need to provide a password (see the documentation). So we should be able to support a similar tag like RequireAdminOnWindows on Linux.