name_regex_keep and name_regex_delete parameters unsupported when deleting registry repository tags in bulk #1246

Description of the problem, including code/CLI snippet

https://docs.gitlab.com/ce/api/container_registry.html#delete-registry-repository-tags-in-bulk indicates that the parameter name_regex seems to be now deprecated in favour of name_regex_keep and name_regex_delete. These two parameters seem to be currently unsupported by the code.

This seems to be defined here https://github.com/python-gitlab/python-gitlab/blob/master/gitlab/v4/objects/__init__.py#L1849