Update variant-schema-compiler to fix build

Fixes https://github.com/flatpak/flatpak/issues/4534

(cherry picked from commit 6cb4a2598e)
This commit is contained in:
Internal Server Error - Gitea: Git with a cup of tea
500 Internal Server Error

Gitea Version: 1.28.0+dev-477-g8b6ad49a5f