Merge pull request DSpace#3281 from DSpace/backport-3035-to-dspace-8_x

[Port dspace-8_x] Set color black on filter section for mobile

src/app/shared/search/search-filters/search-filter/search-filter.component.html

@@ -6,7 +6,7 @@
           [attr.aria-label]="(((collapsed$ | async) ? 'search.filters.filter.expand' : 'search.filters.filter.collapse') | translate) + ' ' + (('search.filters.filter.' + filter.name + '.head') | translate | lowercase)"
           [attr.data-test]="'filter-toggle' | dsBrowserOnly"
   >
-    <span class="h4 d-inline-block text-left mt-auto mb-auto">
+    <span class="h4 d-inline-block text-left mt-auto mb-auto dark:text-white text-dark">
       {{'search.filters.filter.' + filter.name + '.head'| translate}}
     </span>
     <i class="filter-toggle flex-grow-1 fas p-auto"