Update git submodules

* Update docs/submodules/releng from branch 'master'
  - CPERF: Add clean up to CSIT

    Now that we promote Apex artifacts after running CSIT, the snapshots
    will be tainted with the flavor and image used during the CSIT test. We
    should remove those after running CSIT as it may conflict with other
    test suites or user interaction with the snapshots later.

    Change-Id: I874ef145f9df20a9d1471e38698549cbe58dea43
    Signed-off-by: Tim Rozet <trozet@redhat.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 3aa4ff2..bf72656 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 3aa4ff2ae4db3bbfdd139927c0cf0d09a5fdca6a
+Subproject commit bf726569249b773c69c26d0ec8defdd223720c3e