Update git submodules

* Update docs/submodules/functest from branch 'stable/euphrates'
  - Update documentation for Functest

    1. Remove the reference of ubuntu based container
    2. Remove the domino (terminated) and promise (not in F),
       and move fds to features tier

    Conflicts:
        functest/docs/testing/user/userguide/test_overview.rst

    Change-Id: I62af47a3f873f0a77d5f7e0a1df493651c805834
    Signed-off-by: Linda Wang <wangwulin@huawei.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index d45f54a..0642156 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit d45f54a5ea6a2279f42dd4334035a1f9cdfba75e
+Subproject commit 06421562d075f6e9d12a0b43e1dce1982b035d59