Update git submodules

* Update docs/submodules/dovetail from branch 'master'
  - Add all tempest smoke test cases into debug test suite

    Add all tempest smoke test cases into debug test suite.
    Then these test cases can be run by Dovetail on CI.
    The results of CI will help to choose sub test cases from tempest smoke.

    Here use tempest_custom to run all tempest smoke test cases because it can
    support to run a custom defined sub test cases list.
    for Functest tempest_smoke_serial, it always runs whole tempest smoke
    test cases and can't be a subset.

    JIRA: DOVETAIL-595

    Change-Id: Id6358691d2bdef149f16775ce84dcfbf12f5e568
    Signed-off-by: xudan <xudan16@huawei.com>

diff --git a/docs/submodules/dovetail b/docs/submodules/dovetail
index c4131f9..2b9b8e3 160000 (submodule)
--- a/docs/submodules/dovetail
+++ b/docs/submodules/dovetail
@@ -1 +1 @@
-Subproject commit c4131f9a18b9e9eaee75e6e1503d34d6678115a2
+Subproject commit 2b9b8e3340af8087ebdcc1e7f8b33fdff4304ec0