Removed pre-release wheel-only advice in docs/internals/howto-release-django.txt.

The practice since 2.2a1 (2019) has been to upload source distributions
as well.

Author: jacobtylerwalls

docs/internals/howto-release-django.txt

@@ -604,8 +604,7 @@ Now you're ready to actually put the release out there. To do this:
 
    __ https://djangoci.com/job/confirm-release/
 
-#. Upload the release packages to PyPI (for pre-releases, only upload the wheel
-   file):
+#. Upload the release packages to PyPI:
 
    .. code-block:: shell