Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "[QTIP] Delete Euphrates CI jobs"
  - [QTIP] Delete Euphrates CI jobs

    Delete Euphrates CI jobs.

    JIRA: QTIP-292

    Change-Id: I6ab6055fccc2bb7de299bab5732f97565ecef808
    Signed-off-by: zhihui wu <wu.zhihui1@zte.com.cn>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 3a4831f..2623ca8 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 3a4831f66386e14d1ae958145c67609454ce7950
+Subproject commit 2623ca892d49b10316358597818e91fc9a39ba63