Update git submodules

* Update docs/submodules/fuel from branch 'stable/fraser'
  - [maas] Make boot-source-selection ops idempotent
    
    - add `unless` clause;
    - instead of adding a new boot sources, update the existing one,
      assuming standard MaaS installation (always updates id '1');
    
    Change-Id: I2db92a3b14d0588095c69545cbb6977ca109613e
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
    (cherry picked from commit d7ab894b988d8dd6fe49714e0d8d6077e08ebb16)
    

1 files changed, 0 insertions, 0 deletions

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
-Subproject 39c9a0bee27faf0313c79a58103704e94ac91ed
+Subproject e59133c6b910fee71f63855afcb2e39993de7bf