Update git submodules

Update git submodules

* Update docs/submodules/ccsdk/cds.git from branch 'dublin'
  to 2bb065a5f965087c58828a5a8b690838d63da65c
  - Merge "Returning null for unresolved variables" into dublin
  - Returning null for unresolved variables

    When Blueprints Processor was not able to evaluate a variable, it would
    set its value to null.

    The expected behaviour would be to set the value to the default repres-
    entation in the formal notation as defined by Apache Velocity, which is
    a dollar followed by the name of the variable between curly braces. For
    example, if the value of the variable pnf-id could not be evaluated in
    runtime, its value would be defined as the string "${pnf-id}".

    The problem happened during evaluation of the variables that would be
    later sent to the template-meshing code for processing.

    The fix was to add a check before the value was assigned to the varia-
    ble; if the was not null, the assignment will happen normally. Otherwi-
    se, if the evaluation resolves to null, the variable receives the defa-
    ult value (string "${<variable name>}").

    Besides the tests that were put in place to test the code changed for
    this fix, two tests were added to the existing test case of the templa-
    te meshing code, to act as regression test.

    Change-Id: I635afb1eba4c0d45b821811f0119fa6c87ea9542
    Issue-ID: CCSDK-1358
    Signed-off-by: ottero <rodrigo.ottero@est.tech>