Update git submodules

Update git submodules

* Update docs/submodules/snaps from branch 'master'
  - Merge "Fixed timeout logic when attaching/detaching volumes."
  - Fixed timeout logic when attaching/detaching volumes.

    The timeout logic in nova_utils.attach_volume() and detach_volume()
    was not correct which may have been the root cause behind the issue
    FUNCTEST-927. Timeout in both attach and detach is no longer
    optional.

    Also added a test to attach and detach without timeout as that path
    was never tested. Updated associated test documentation as well.

    JIRA: SNAPS-263
    JIRA: FUNCTEST-927

    Change-Id: Iea3aeab59c378917fbd175d673113e8d30e2e4b9
    Signed-off-by: spisarski <s.pisarski@cablelabs.com>