Update git submodules

* Update openstacksdk from branch 'master'
  to 568921ce5b50275061c5dd0ba7180842f3c157a7
  - tox: Correct functional test factors
    
    We are running functional tests in zuul without a 'pyNN' factor (e.g.
    'tox -e functional'). For this to work, we need to allow an empty
    factor, i.e. we want:
    
      [testenv:functional{,-py310}]
    
    rather than:
    
      [testenv:functional{-py310}]
    
    (note the missing comma)
    
    Unfortunately we missed this as tox 4 has a currently unaddressed
    regression [1] that results in it running the base testenv in the case
    there is only a partial factor match. That needs to be fixed for avoid
    this biting us again the future, but we can at least fix it for now.
    
    [1] tox-dev/tox#3219
    
    Change-Id: Ib9f65a4523222f1224d51534c5061f90501b59d3
    Signed-off-by: Stephen Finucane <stephenfin@redhat.com>