Fix TuyaDPType.VALUE payload

[javicalle]

During the analisys of #1554 I have realized that something was wrong in the MCU logs for the LevelControl.
Comparing the status report from the device against the command send from HA it was clear that something don't work as expected:

2022-10-23 13:57:40.824 DEBUG (MainThread) [zigpy.zcl] [0x6F8F:1:0xef00] Received command 0x01 (TSN 101): get_data(data=
TuyaCommand(status=0, tsn=71, datapoints=[TuyaDatapointData(dp=2, data=TuyaData(dp_type=<TuyaDPType.VALUE: 2>, function=0, raw=b'\xfa\x00\x00\x00', *payload=250))]))

2022-10-23 13:57:41.933 DEBUG (MainThread) [zigpy.zcl] [0x6F8F:1:0xef00] tuya_command: 
TuyaCommand(status=0, tsn=97, datapoints=[TuyaDatapointData(dp=2, data=TuyaData(dp_type=<TuyaDPType.VALUE: 2>, function=0, raw=b'\x00\x00\x02\x8a', *payload=2315386880))])

Once identified and the fixed, the tests that validated against the observed value have also had to be fixed.

The fix only affects to the MCU commands sended with a TuyaDPType.VALUE (i.e: current_level for the LevelControl cluster). I can't be a breaking change because the current implementation is wrong. I don't think that could be the reason for some weird behavior in dimmers but I can't validate by myself.

[codecov-commenter]

Codecov Report

Base: 83.16% // Head: 83.16% // No change to project coverage 👍

Coverage data is based on head (7e52934) compared to base (05ee519).
Patch coverage: 100.00% of modified lines in pull request are covered.

Additional details and impacted files

@@           Coverage Diff           @@
##              dev    #1984   +/-   ##
=======================================
  Coverage   83.16%   83.16%           
=======================================
  Files         248      248           
  Lines        7819     7819           
=======================================
  Hits         6503     6503           
  Misses       1316     1316           

Impacted Files	Coverage Δ
zhaquirks/tuya/mcu/__init__.py	100.00% <100.00%> (ø)

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[coveralls]

Pull Request Test Coverage Report for Build 3614545245

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 83.169%

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Totals
Change from base Build 3577832421:	0.0%
Covered Lines:	6503
Relevant Lines:	7819

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💛 - Coveralls

[javicalle]

Thanks David