ci: Add explicit dependency on "which"

The xvfb-run script depends on it, but it seems Fedora packages ended up
forgetting about it.

diff --git a/.gitlab-ci/Dockerfile b/.gitlab-ci/Dockerfile
index c4c66c203b1eefafadfd2cf41d1bfd38d094ec0d..c940ef6eaf3ea2d8bbe0846f72b53359bbdf118a 100644 (file)
--- a/.gitlab-ci/Dockerfile
+++ b/.gitlab-ci/Dockerfile
@@ -59,6 +59,7 @@ RUN dnf -y install \
     vulkan-devel \
     wayland-devel \
     wayland-protocols-devel \
+    which \
     xorg-x11-server-Xvfb
 
 ARG HOST_USER_ID=5555