Documented how to rename get_query_set if you are a library author
Updated docs/spelling_wordlist
Fixed typo in docs/ref/contrib/sites.txt
Fixed #23426 -- Allowed parameters in migrations.RunSQL

Thanks tchaumeny and Loic for reviews.
Fixed #23482 -- Added SingleObjectMixin.query_pk_and_slug

Enabling the attribute causes get_object() to perform its lookup
using both the primary key and the slug.