devel/ghq: update to 1.9.4

Changes: https://github.com/x-motemen/ghq/releases/tag/v1.9.0
Changes: https://github.com/x-motemen/ghq/releases/tag/v1.9.1
Changes: https://github.com/x-motemen/ghq/releases/tag/v1.9.2
Changes: https://github.com/x-motemen/ghq/releases/tag/v1.9.3
Changes: https://github.com/x-motemen/ghq/releases/tag/v1.9.4