Added account featured tags API (#11817)

app/controllers/api/v1/accounts/featured_tags_controller.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+class Api::V1::Accounts::FeaturedTagsController < Api::BaseController
+  before_action :set_account
+  before_action :set_featured_tags
+
+  respond_to :json
+
+  def index
+    render json: @featured_tags, each_serializer: REST::AccountFeaturedTagSerializer
+  end
+
+  private
+
+  def set_account
+    @account = Account.find(params[:account_id])
+  end
+
+  def set_featured_tags
+    @featured_tags = @account.featured_tags
+  end
+end