Update gitlab-ci.sh

Show paths in it, to investigate (just a test)

gitlab-ci.sh

@@ -12,7 +12,12 @@ comp=${1:-system}
 opam init --comp="${comp}"
 eval `opam config env`
 
-# Versions
+# Versions and files
+echo "Trees"
+echo "."
+tree .
+echo "~"
+tree ~
 echo "= Versions ="
 echo "opam --version"
 opam --version