Update git submodules

* Update docs/submodules/fuel from branch 'stable/fraser'
  - Update release notes for 6.2

    Change-Id: Ibd168ef31af1f8a9a2c128ce8a8e95a5c231a917
    Signed-off-by: Cristina Pauna <cristina.pauna@enea.com>
    (cherry picked from commit ea9cf5304b649298c40155714a4374724aec1835)

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index c6de902..56a5525 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit c6de9021d6b387e24363dcf4eb35692ef82d439f
+Subproject commit 56a5525a3ceafd6cbdeee239dc17c6e0a1a94f69