build(deps): bump libglnx from b38235a to 87f2768

Bumps [libglnx](https://github.com/GNOME/libglnx) from `b38235a` to `87f2768`.
- [Commits](GNOME/libglnx@b38235a...87f2768)

---
updated-dependencies:
- dependency-name: libglnx
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>