Fix: Increase caselight PWM frequency to eliminate LM3407MY inductor whine

[a-github-username]

Problem:
Despite the LM3407MY having an internal clock rate beyond the audible range (300kHz to 1MHz), the MCU controller PWM signal to the actual LM3407MY chip was set to 4kHz. This was switching the entire LM3407MY chip off and on in the audible range which was causing the L1 inductor to "whine" at 4kHz.

So the assumption that just because the LED control chip has a clock rate beyond the audible range doesn't mean that it can't necessarily have inductor whine given the entire chip is essentially subject to the cycle rate of the MCU PWM pinout. Therefore the internal switching frequency of the LED controller is actually completely irrelevant here.

The fix:
[output_pin caselight]
pin: PE6
pwm:true
hardware_pwm: False
value: 0.20 #startup value
shutdown_value: 0
#value:1
cycle_time: 0.00025 (4kHz) --->>> 0.0000164 (61kHz -- I chose a prime number to further prevent any resonance frequencies)

**Note that I contacted LDO support on the West3D Discord channel and provided video evidence of the exact issue.