Unpack client_options with **, for ruby 3 compatibility

With ruby 3, there are some changes with keyword arguments: https://www.ruby-lang.org/en/news/2019/12/12/separation-of-positional-and-keyword-arguments-in-ruby-3-0/

This was causing errors on the ruby 3 branch, so we fixed it there, and want to push it upstream, as to keep our ruby 3 branch as small as possible.

Related to #358804 (closed)