feat: implement search filter for User REST endpoint

We need the search filter to implement a user complete field in the
dashboard.

program/views.py

@@ -25,6 +25,7 @@ from itertools import pairwise
 from textwrap import dedent
 
 from drf_spectacular.utils import OpenApiResponse, extend_schema, extend_schema_view
+from rest_framework import filters as drf_filters
 from rest_framework import mixins, permissions, status, viewsets
 from rest_framework.exceptions import ValidationError
 from rest_framework.pagination import LimitOffsetPagination
@@ -263,6 +264,8 @@ class APIUserViewSet(
     permission_classes = [permissions.DjangoModelPermissionsOrAnonReadOnly]
     serializer_class = UserSerializer
     queryset = User.objects.all()
+    filter_backends = [drf_filters.SearchFilter]
+    search_fields = ["username", "first_name", "last_name", "email"]
 
     def get_queryset(self):
         queryset = super().get_queryset()