[DPB]Fix return code in case of failure (#3389)

* [DPB]Fix return code in case of failure

* Updating UT

Author: dgsudharsan

config/main.py

@@ -4697,7 +4697,7 @@ def breakout(ctx, interface_name, mode, verbose, force_remove_dependencies, load
     except Exception as e:
         click.secho("Failed to break out Port. Error: {}".format(str(e)), fg='magenta')
 
-        sys.exit(0)
+        sys.exit(1)
 
 def _get_all_mgmtinterface_keys():
     """Returns list of strings containing mgmt interface keys

tests/config_dpb_test.py

@@ -350,7 +350,7 @@ def test_config_breakout_extra_table_warning(self, breakout_cfg_file, sonic_db):
             commands["breakout"], ['{}'.format(interface), '{}'.format(newMode), '-v', '-y'], obj=obj)
 
         print(result.exit_code, result.output)
-        assert result.exit_code == 0
+        assert result.exit_code == 1
         assert 'Below Config can not be verified' in result.output
         assert 'UNKNOWN_TABLE' in result.output
         assert 'Do you wish to Continue?' in result.output