Update git submodules

* Update docs/submodules/functest from branch 'stable/euphrates'
  - Select Rally 0.9.1

    stable/rally forces to use a newer version os-faults which is not
    synced and is incompatible by default. Then it selects the rally
    version tested as the community hugely updates its stable branches.

    JIRA: PROMISE-88

    Change-Id: I6c15f71737af5edac53972a8463cc166bd096a7e
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 249864c..e1ac082 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 249864cfb9c4b08e95a7a616c09f2c36b5a56c5d
+Subproject commit e1ac08297e711ab4a49c062fd30f2ef9379af8a6