New default themes require workarounds being added to several unit tests, as they often alter default WordPress behaviour. To avoid ongoing maintenance issues, this change switches to a minimal theme when running tests.
This change also removes the old workarounds for default themes.
Fixes#31550.
git-svn-id: https://develop.svn.wordpress.org/trunk@38858 602fd350-edb4-49c9-b593-d223f7449a82
Gary Pendergast