fix: Content slider traget details vertical alignement not centered - MEED-10107 - Meeds-io/meeds#3964

prior to this change, the content slider info wasn't vertically centered due to missing flex display css property,
This PR ensures to add the needed class helper to vertically center the details.

Author: hakermi

content-webapp/src/main/webapp/vue-app/news-list-view/components/views/NewsSliderView.vue

@@ -41,7 +41,7 @@
             :alt="item?.properties?.featuredImage?.altText || ''"
             class="articleImage object-fit-cover width-full full-height">
           <v-container class="slide-text-container d-flex text-center">
-            <div class="flex flex-column carouselNewsInfo">
+            <div class="d-flex flex-column carouselNewsInfo">
               <div
                 :class="$vuetify.rtl && 'l-0' || 'r-0'"
                 class="flex flex-row position-absolute">