Issue #3365435 by andy-blum, bernardm28, chrisfromredfin, mike.roman: Update markup classnames

css/pb.css

sveltejs/public/build/bundle.js

sveltejs/public/build/bundle.js.map

sveltejs/src/Filter.svelte

sveltejs/src/ImageCarousel.svelte

sveltejs/src/ModulePage.svelte

sveltejs/src/Project/ActionButton.svelte

sveltejs/src/Project/Categories.svelte

sveltejs/src/Project/LoadingEllipsis.svelte

sveltejs/src/Project/Project.svelte

sveltejs/src/ProjectBrowser.svelte

sveltejs/src/ProjectGrid.svelte

sveltejs/src/Tabs.svelte

.../FunctionalJavascript/ProjectBrowserExamplePluginTest.php

...rc/FunctionalJavascript/ProjectBrowserInstallerUiTest.php

tests/src/FunctionalJavascript/ProjectBrowserPluginTest.php

tests/src/FunctionalJavascript/ProjectBrowserUiTest.php

.../src/FunctionalJavascript/ProjectBrowserUiTestJsonApi.php

tests/src/FunctionalJavascript/ProjectBrowserUiTestTrait.php