Issue #3405660 by smustgrave, quietone, Wim Leers, larowlan, lauriii: Remove tour from themes

core/modules/tour/css/theme/claro-tour.theme.css

core/modules/tour/css/theme/claro-tour.theme.pcss.css

core/modules/tour/css/theme/stable9-tour.module.css

core/modules/tour/js/theme/tour.js

core/modules/tour/tour.libraries.yml

core/modules/tour/tour.module

...s/Core/Asset/ResolvedLibraryDefinitionsFilesMatchTest.php

...pal/KernelTests/Core/Theme/Stable9LibraryOverrideTest.php

.../KernelTests/Core/Theme/StableLibraryOverrideTestBase.php

core/themes/claro/claro.info.yml

core/themes/claro/claro.libraries.yml

core/themes/olivero/css/components/site-header.css

core/themes/olivero/css/components/site-header.pcss.css

core/themes/stable9/stable9.info.yml

core/themes/stable9/stable9.libraries.yml