Fix test Client headers for Django 4.2 (#1465)

* Fix test Client headers for Django 4.2

* Lazy import pkg_resources

since it could be quite heavy

* Remove use of pkg_resources altogether

graphene_django/utils/testing.py

@@ -4,6 +4,7 @@
 from django.test import Client, TestCase, TransactionTestCase
 
 from graphene_django.settings import graphene_settings
+from graphene_django.utils.utils import _DJANGO_VERSION_AT_LEAST_4_2
 
 DEFAULT_GRAPHQL_URL = "/graphql"
 
@@ -55,8 +56,14 @@ def graphql_query(
         else:
             body["variables"] = {"input": input_data}
     if headers:
+        header_params = (
+            {"headers": headers} if _DJANGO_VERSION_AT_LEAST_4_2 else headers
+        )
         resp = client.post(
-            graphql_url, json.dumps(body), content_type="application/json", **headers
+            graphql_url,
+            json.dumps(body),
+            content_type="application/json",
+            **header_params
         )
     else:
         resp = client.post(

graphene_django/utils/utils.py

@@ -1,5 +1,6 @@
 import inspect
 
+import django
 from django.db import connection, models, transaction
 from django.db.models.manager import Manager
 from django.utils.encoding import force_str
@@ -145,3 +146,8 @@ def bypass_get_queryset(resolver):
     """
     resolver._bypass_get_queryset = True
     return resolver
+
+
+_DJANGO_VERSION_AT_LEAST_4_2 = django.VERSION[0] > 4 or (
+    django.VERSION[0] >= 4 and django.VERSION[1] >= 2
+)