vtest: Temporary debugging in u0.vtc

For some reason this is failing on some platforms reporting on VTEST.

bin/varnishtest/tests/u00000.vtc

@@ -4,11 +4,15 @@ shell "varnishd -b 127.0.0.1:80 -C 2> ${tmpdir}/_.c"
 
 shell {
 	varnishd -n ${tmpdir}/no_keep -C -b 127.0.0.1:80 2> no_keep.c
+	ls -l
+	set -x
 	test -s no_keep.c && ! test -d no_keep
 }
 
 shell {
 	varnishd -n ${tmpdir}/keep -p debug=+vcl_keep -C -b 127.0.0.1:80 2> keep.c
+	ls -l
+	set -x
 	test -s keep.c && test -d keep
 }