Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Fix get_port_by_name in ims testcases"
  - Fix get_port_by_name in ims testcases

    Now there isn't a function named get_port_by_name in [1].
    Use get_port to replace it.

    [1]: https://git.opnfv.org/snaps/tree/snaps/openstack/utils/neutron_utils.py

    Change-Id: Ide5d6b497092f66abe6b0452841007808ee908e6
    Signed-off-by: Alex Yang <yangyang1@zte.com.cn>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 96eb11c..506ef8b 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 96eb11c116a15893a8e6af780fde3d675ad1b4d7
+Subproject commit 506ef8bdcb772637be4dc01c5afc0e583f7ae3d3