feat/tup-630: Migrate django.cms.blog.app.item to core-cms (#734)

* migrated article time css into blog.app.item

* fix: custom selector syntax

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Co-authored-by: Wesley Bomar <wbomar@tacc.utexas.edu>
Co-authored-by: Wesley B <62723358+wesleyboar@users.noreply.github.com>

taccsite_cms/static/site_cms/css/src/_imports/components/django.cms.blog.app.item.css

@@ -167,6 +167,13 @@ Styleguide Components.DjangoCMS.Blog.App.Item
 
 /* Content */
 
+/* <time> as a header tag may not be relevant as of Oct. 17, 23 */
+:--article-item time:not(:is(h1, h2, h3, h4, h5, h6) *) {
+  color: var(--global-color-accent--secondary);
+  font-weight: var(--medium);
+  text-transform: uppercase;
+}
+
 :--article-item .blog-lead {
   @extend %x-truncate--many-lines;
   --lines: 4;