[NRRPLT-5496] Use default timestep from CLE.

This patch removes the hardcoded 20ms timestep value and instead
references the default value set in the CLE.

Change-Id: Iaa17d20a39b6c6b0b3fd271a19db3ddff42b6fe6

hbp_nrp_music_interface/hbp_nrp_music_interface/launch/MUSICBrainProcess.py

@@ -27,6 +27,7 @@ A distributed brain process that can be launched standalone on remote hosts.
 from hbp_nrp_cle.brainsim import config
 from hbp_nrp_cle.brainsim.pynn import simulator as sim
 from hbp_nrp_cle.brainsim.pynn.PyNNControlAdapter import PyNNControlAdapter
+from hbp_nrp_cle.cle.ClosedLoopEngine import ClosedLoopEngine
 import hbp_nrp_cle.tf_framework.config as tf_config
 
 from hbp_nrp_commons.generated import bibi_api_gen
@@ -98,8 +99,10 @@ class MUSICBrainProcess(object):
 
         self._proxies = xml_factory.create_proxies(music_xml)
 
-        # extract the simulation timestep from the BIBI or default to 20 ms
-        self._timestep = float(self._bibi.timestep) if self._bibi.timestep is not None else 20.0
+        # extract the simulation timestep from the BIBI if set or default to CLE value (in ms)
+        self._timestep = ClosedLoopEngine.DEFAULT_TIMESTEP * 1000.0
+        if self._bibi.timestep:
+            self._timestep = float(self._bibi.timestep)
 
     def run(self):
         """