Log Message:
devel/ruby-zeitwerk: update to 2.6.18

2.6.17 (2024-07-29)

* Fix log message when eager loading a directory ends.

2.6.18 (2024-09-02)

* Fixes a bug in which projects reopening the main namespace of a gem
  dependency managed by its own Zeitwerk loader could not reload the
  constants they added to that external namespace.