title: Django Rest-Framework search-fields wont work inside @action
body: <p>I'm trying to use the search field offered by DRF inside of an action, but it seems to not work. I had a similar problem paginating inside of the action but found a solution. My guess is that it's overriding the ModelViewSet so I have to manually add the filtering, but is there a way to use the same search_fields offered by DRF.  Here's my code:</p>
  <pre><code>class XViewSet(ModelViewSet):
      queryset = X.objects.all()
      serializer_class = XSerializer
      permission_classes = [IsAdminUser]
      filter_backends = (SearchFilter,OrderingFilter)
      search_fields = ['a','b','c','d']
      @action(detail=False, methods=['GET'], permission_classes=[IsAuthenticated])
      def me(self, request):
          query = X.objects.filter(ex_id=request.user.id)
          if request.method == 'GET':
              
              serializer = XSerializer(query, many=True)
              return Response(serializer.data)
  </code></pre>
  <p>Any help is appreciated, Thank you :)</p>