Log Message:
www/ruby-rack-cache: update to 1.15.0

1.15.0 (2023-12-09)

What's Changed

* Update reference to MiniTest -> Minitest by @Matt-Yorkley in #17
* Add test (and fix support for) for Rack v2.1.x. by @ioquatix in #19

New Contributors

* @Matt-Yorkley made their first contribution in #17