category archive url ending with "/0" should be 404

[obache]

First, if URL is "/category/cat1/0", first, it is recognized as category_name="cat1/0",
then "is_category=true" and category archive template should be selected.

But for really query, category_name="0" and empty($q["category_name"])==true,
so it is recognized as "category is not specified", then tax_query will be empty, and queried_object==null.

Finally, category template will be confused.
No category is selected, any category related information are broken (maybe rise warnings or errors).
Any recent posts of any public post types will be displayed even if its post_type dose not belong to core 'category' taxonomy.

[obache]

questioned codes in WP_Query::parse_tax_query().

 if ( $t->query_var && ! empty( $q[ $t->query_var ] ) ) { 

whereas $t->query_var is 'category_name', and $q['category_name'] is 0;

should it be strlen( $q[ $t->query_var ] ) > 0 instead of ! empty( $q[ $t->query_var ] ) ?

[obache]

maybe related to #50149