Fix switch state representation for scenes that turn switches off

[tstabrawa]

Proposed change

This change fixes a bug whereby switch scenes that are configured to turn the switch off (i.e. with data_1 == 0x00) would be marked as having turned the switch on in MQTT, despite the switch actually turning off.

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request:
• Related to discussion: How do I define a scene to turn a switch off? #338

Note: I wasn't sure if other device types that have on-off states (e.g. KeypadLinc, Outlet) behaved the same (as I don't have these devices), so this change only applies to the Switch device type. Let me know if you know which other devices work this way and if you'd like me to add changes for them to this PR.

Confirmed no new flake8 errors, pylint errors, or code coverage gaps. All tests passing. Also, confirmed new test (test_handle_group_cmd) fails prior to applying fix:

================================================================================ FAILURES ================================================================================
___________________________________________________________ Test_Base_Config.test_handle_group_cmd[17-0-False] ___________________________________________________________

self = <test_SwitchDev.Test_Base_Config object at 0x7f9370aa5390>, test_device = <insteon_mqtt.device.Switch.Switch object at 0x7f937055b910>, cmd1 = 17, entry_d1 = 0
expected = False

    @pytest.mark.parametrize("cmd1, entry_d1, expected", [
        (0x11, None, None),
        (0x11, 0xFF, True),
        (0x11, 0x00, False),
        (0x13, None, None),
        (0x13, 0xFF, False),
        (0x13, 0x00, False),
    ])
    def test_handle_group_cmd(self, test_device, cmd1, entry_d1, expected):
        with mock.patch.object(IM.Signal, 'emit'):
            # Build the msg to send to the handler
            to_addr = test_device.addr
            from_addr = IM.Address(0x04, 0x05, 0x06)
            flags = IM.message.Flags(IM.message.Flags.Type.ALL_LINK_CLEANUP,
                                     False)
            msg = IM.message.InpStandard(from_addr, to_addr, flags, cmd1, 0x01)
            # If db entry is requested, build and add the entry to the dev db
            if entry_d1 is not None:
                db_flags = IM.message.DbFlags(True, False, True)
                entry = IM.db.DeviceEntry(from_addr, 0x01, 0xFFFF, db_flags,
                                          bytes([entry_d1, 0x00, 0x00]))
                test_device.db.add_entry(entry)
            # send the message to the handler
            test_device.handle_group_cmd(from_addr, msg)
            # Test the responses received
            calls = IM.Signal.emit.call_args_list
            if expected is not None:
                print(calls)
>               assert calls[0][1]['is_on'] == expected
E               assert True == False

tests/device/test_SwitchDev.py:113: AssertionError
-------------------------------------------------------------------------- Captured stdout call --------------------------------------------------------------------------
[call(<insteon_mqtt.device.Switch.Switch object at 0x7f937055b910>, is_on=True, level=None, mode=<Mode.NORMAL: 'normal'>, button=1, reason='scene')]
======================================================================== short test summary info =========================================================================
FAILED tests/device/test_SwitchDev.py::Test_Base_Config::test_handle_group_cmd[17-0-False] - assert True == False
===================================================================== 1 failed, 689 passed in 10.74s =====================================================================

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• Tests have been added to verify that the new code works.
• Code documentation was added where necessary - N/A

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated - N/A

[krkeegan]

Perfect, thank you for this.