Fixes:

- Use DRF ImageField, not FileField
- Ensure that permissions get updated correctly in 'test' mode
- Allow file upload in the APITester class

InvenTree/users/apps.py

@@ -13,7 +13,7 @@ class UsersConfig(AppConfig):
 
     def ready(self):
 
-        if canAppAccessDatabase():
+        if canAppAccessDatabase(allow_test=True):
 
             try:
                 self.assign_permissions()

InvenTree/users/models.py

@@ -276,7 +276,7 @@ def update_group_roles(group, debug=False):
 
     """
 
-    if not canAppAccessDatabase():
+    if not canAppAccessDatabase(allow_test=True):
         return
 
     # List of permissions already associated with this group