Check Docker CLI availability on WSL agent

scripts/woodpecker-cross-test.sh

@@ -8,6 +8,7 @@ RESULTS="${HOME}/staticlink-ci-artifacts/${CI_REPO_NAME:-StaticLink.Avalonia}/${
 mkdir -p "$RESULTS/environment"
 df -h .
 free -h
+command -v docker
 docker version
 if [ "$(docker info --format '{{.OSType}}/{{.Architecture}}')" != "linux/x86_64" ]; then
   echo "Requires a Linux x86_64 Docker daemon on the WSL agent" >&2