Add note to FAQ in docs (#162)

* Add note to FAQ in docs

Spent some time while implementing django-hosts and fixing our tests, so I thought it was worth adding here

* Update docs/faq.rst

* Update docs/faq.rst

* Update docs/faq.rst

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Co-authored-by: Hasan Ramezani <hasan.r67@gmail.com>

docs/faq.rst

@@ -21,3 +21,16 @@ Also, you have to install `django-debug-toolbar 0.9.X`_ or higher.
 
 .. _`Django Debug toolbar`: https://github.com/django-debug-toolbar/django-debug-toolbar/
 .. _`django-debug-toolbar 0.9.X`: http://pypi.python.org/pypi/django-debug-toolbar
+
+
+My tests using client.post(...) are failing now, what should I do?
+--------------------------------------------------------------
+
+Yes, django-hosts might make your existing pytest tests fail if you are using
+client.post(...). All you need to do is to set the correct SERVER_NAME on that call
+depending on the host that should handle the call
+
+.. code-block:: python
+
+    client.post(..., SERVER_NAME='api-server.something')
+