Fix whitespace in SNMP docstring (#322)

Remove trailing whitespace to resolve flake8 W293 warning

Author: ronier83

cterasdk/edge/snmp.py

@@ -56,7 +56,7 @@ def disable(self):
     def get_configuration(self):
         """
         Get current SNMP configuration
-        
+
         :return: Current SNMP configuration
         :rtype: cterasdk.common.object.Object
         """