This update for gifsicle fixes the following issues:

Update to version 1.93:

* Fix security bug on certain resize operations with `--resize-method=box`
* Fix problems with colormapless GIFs.

Update to version 1.92

* Add `--lossy` option from Kornel Lipiński.
* Remove an assertion failure possible with
  `--conserve-memory` + `--colors` + `--careful`.