Update git submodules

* Update docs/submodules/functest from branch 'stable/fraser'
  - Print the stack traceback when cleaning juju_epc

    Change-Id: If32557a4384cafd67b7c294f8c0592ee2769b1a5
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>
    (cherry picked from commit b2b1be21af5de2dd88092be268ae5f817608ecd1)

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 2da8034..526c0d5 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 2da803403ecd829eeeaa787155972e956027b318
+Subproject commit 526c0d5fc77d996b255533b21da4581622568254