vala test app fails to build with vala master

As of vala@1a4a14d5, the test app fails to build. On #vala, @albfan and @ricotz suggested doing the same as gitg@7be88eab and gitg@960c9bed This is the build log: https://gnome.pages.gitlab.gnome.org/-/gnome-build-meta/-/jobs/157719/artifacts/logs/gnome/sdk-vte/17542805-build.29595.log

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information