[FIX] web: restore tags' names color on kanban

Those were broken with recent m2m tags refactoring.

addons/web/static/src/scss/kanban_view.scss

@@ -230,6 +230,7 @@
                 font-size: 11px;
                 font-weight: 500;
                 background-color: transparent;
+                color: inherit;
                 @include o-kanban-tag-color;
 
                 span {