Update git submodules

* Update docs/submodules/functest from branch 'stable/danube'
  - Switch TestcaseBase to TestCase

    It partially reverts "Rename TestCasesBase into TestcaseBase" [1] and
    removes the useless suffix too.

    [1] https://gerrit.opnfv.org/gerrit/#/c/25391/

    Change-Id: Iddf2ec8d6c1dafe6e4c6713c2e69969613317471
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>
    (cherry picked from commit 407d27585f109e3381bb49041abc49a14b7b5bfe)

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 3a86d68..5112760 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 3a86d68a88ceb80fd335c2ed689be1cc1b41bc6a
+Subproject commit 5112760fe2ca1e4d31f368235c4aee87e7577e5f