Potential Celsius/Fahrenheit conversion/rounding issue: some Fahrenheit temperatures can't be set and/or are set incorrectly by a degree.
**Describe The Bug:**
I think that something is wrong in terms of rounding/converting between Celsius and Fahrenheit. I'm only able to set certain Fahrenheit temperatures through HomeKit, and sometimes the temperature in LG is off by one degree F compared to HomeKit.

I, Fahrenheit, can set 61, 63, 64, 66, 68, 70, 72, 73, 75, 77, 79, 81, 82, 84, and 86. But I can't set 60, 62, 65, 67, 71, 74, 76, 78, 80, 83, or 85.

When I set 61 in HomeKit, my LG is set to 60. When I set 63, my LG is set to 62. 64, 66, 68, 70, and 72 all set correctly. 73 on HomeKit sets 74 on LG, 75 sets 76 on LG...

**To Reproduce:**
Set the temperature in Home, observe that some temperatures are incorrect and some temperatures are off by a degree.

**Expected behavior:**
I should be able to set any degree Fahrenheit, and the temperature in Home should map to the temperature in LG.

**Logs:**
See https://github.com/nVuln/homebridge-lg-thinq/issues/203
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**Plugin Config:**

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**Screenshots:**
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**Environment:**

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