Update git submodules

Update git submodules

* Update docs/submodules/functest from branch 'stable/fraser'
  - Allow overriding default storage protocol

    It adds a new env var STORAGE_PROTOCOL to override storage_protocol
    in tempest. The default value is unchanged [1].

    [1] https://docs.openstack.org/tempest/latest/sampleconf.html

    Co-Authored-By: Viktor Tikkanen <viktor.tikkanen@nokia.com>
    Change-Id: I19e4e25212b6f6176e3b967e01eb634c15e4d474
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>
    (cherry picked from commit a561c6ca316feb1a203327aa729ac0317f70df48)