Issue #3307674 by tim.plunkett: Clean up ProjectBrowserSourceInterface and Project object

...evel/src/Plugin/ProjectBrowserSource/RandomDataPlugin.php

src/Plugin/ProjectBrowserSource/DrupalCore.php

src/Plugin/ProjectBrowserSource/MockDrupalDotOrg.php

src/Plugin/ProjectBrowserSourceInterface.php

src/ProjectBrowser/Project.php

src/ProjectBrowser/ProjectsResultsPage.php

sveltejs/public/build/bundle.js

sveltejs/public/build/bundle.js.map

sveltejs/src/ModulePage.svelte

sveltejs/src/Project/ActionButton.svelte

sveltejs/src/Project/Categories.svelte

sveltejs/src/Project/Project.svelte

tests/src/Kernel/CoreExperimentalLabelTest.php