Fix bug 1536: incorrect check SDNC status in EPA03

Modified the way to check the successful creation of SDNC in 'Check for SDNC' keyword.
Corrected check on metric (should be 1) in 'Check If SDNC Is Available' keyword.

Change-Id: I7f23dc9033caec8ac6ab3d00be577912a1bfa0fa
Signed-off-by: aguilarherna <daguilarh@indra.es>
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>