Update index.mdx to resolve ValueError (#10564)

* Update index.mdx

Changed 'endpoint' to 'function_name' under how to name transactions showing in Sentry Tracing.

Resolves a ValueError when configuring Sentry for Django:
ValueError: Invalid value for transaction_style: endpoint (must be in ('function_name', 'url'))

* Update docs/platforms/python/integrations/django/index.mdx

---------

Co-authored-by: Liza Mock <lizka920@gmail.com>

docs/platforms/python/integrations/django/index.mdx

@@ -123,10 +123,10 @@ You can pass the following keyword arguments to `DjangoIntegration()`:
 
 - `transaction_style`:
 
-  How to name transactions showing up in Sentry tracing.
+  How to name transactions that show up in Sentry tracing.
 
   - `"/myproject/myview/<foo>"` if you set `transaction_style="url"`.
-  - `"myproject.myview"` if you set `transaction_style="endpoint"`.
+  - `"myproject.myview"` if you set `transaction_style="function_name"`.
 
   The default is `"url"`.