tests: Update to the latest commit on libcgroup-tests release-2.0

Reported-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>

diff --git a/tests b/tests
index 918443bd89efb807d92c1754b0b3fbff4bd3304f..45659c840b69e53b379163e6af9f7c3ee706b3b9 160000 (submodule)
--- a/tests
+++ b/tests
@@ -1 +1 @@
-Subproject commit 918443bd89efb807d92c1754b0b3fbff4bd3304f
+Subproject commit 45659c840b69e53b379163e6af9f7c3ee706b3b9