devel/ruby-kgio: update to 2.11.4

kgio 2.11.4 / 2021-05-25 23:24 UTC

  This release fixes compatibility with GC.compact on Ruby 3.x.
  Thanks to Ngan Pham for the patch and Aaron Patterson for the
  feedback:

    https://yhbt.net/kgio-public/CAAvYYt5Z5f2rMuXO5DMpR1-6uRvu_gXKDvqcyoZ+oNcLiTH39g@mail.gmail.com/T/

  kgio remains obsolete and deprecated, and it's primary dependent
  will be updated to not depend on it in the future.

(taca)