Update git submodules

* Update docs/submodules/msb/apigateway.git from branch 'master'
  to 71531542ea1f5def5b946c6b0a5b0a176718ffb4
  - Merge "Automation adds release-notes.rst"
  - Automation adds release-notes.rst
    
    Issue-ID: CIMAN-33
    
    Change-Id: I92632358149a2e1b50045549b2bbe468dd5e6ca1
    Signed-off-by: lf-jobbuilder <releng+lf-jobbuilder@linuxfoundation.org>
    
1 file changed