Skip authorization check when searching for labels on IssuableFinder

app/finders/issuable_finder.rb

@@ -126,7 +126,7 @@ class IssuableFinder
 
     @labels =
       if labels? && !filter_by_no_label?
-        LabelsFinder.new(current_user, project_ids: projects, title: label_names).execute
+        LabelsFinder.new(current_user, project_ids: projects, title: label_names).execute(skip_authorization: true)
       else
         Label.none
       end
@@ -273,7 +273,7 @@ class IssuableFinder
         items = items.with_label(label_names, params[:sort])
 
         if projects
-          label_ids = LabelsFinder.new(current_user, project_ids: projects).execute.select(:id)
+          label_ids = LabelsFinder.new(current_user, project_ids: projects).execute(skip_authorization: true).select(:id)
           items = items.where(labels: { id: label_ids })
         end
       end

app/finders/labels_finder.rb

@@ -22,7 +22,7 @@ class LabelsFinder < UnionFinder
       label_ids << project.group.labels if project.group.present?
       label_ids << project.labels
     else
-      label_ids << Label.where(group_id: projects.group_ids.uniq)
+      label_ids << Label.where(group_id: projects.group_ids)
       label_ids << Label.where(project_id: projects.select(:id))
     end