Update git submodules

* Update docs/submodules/aai/aai-common.git from branch 'master'
  to 6915f57d07f466a6dd54be693b2af2cec9b8e0c1
  - AAI-common sonar fixes
    
    Issue-ID: AAI-2786
    Change-Id: Ia37e660886fce56c8ab5c53888fcbf265692a359
    Signed-off-by: David Brilla <david.brilla@tieto.com>
    
diff --git a/docs/submodules/aai/aai-common.git b/docs/submodules/aai/aai-common.git
index 71d81fa..6915f57 160000
--- a/docs/submodules/aai/aai-common.git
+++ b/docs/submodules/aai/aai-common.git
@@ -1 +1 @@
-Subproject commit 71d81fa49428fcd2080844482e4e1205a9481ae4
+Subproject commit 6915f57d07f466a6dd54be693b2af2cec9b8e0c1