Same value for R20 and R21

R20 and R21 have different values:

• R20 = 190R, serial resistor for D7 green LED 1.95V
• R21 = 160R, serial resistor for D8 green LED 2.2V

The distinct value will compensate the luminosity disparity between the two LEDs. But having a difference in luminosity between two LEDs is not a critical issue and the MCU outputs used for the LEDs are both PWMs, so the luminosity could be dimmed / calibrated. The two resistors could have the same value -> BOM simplification.

Don't do by HW what you can do by SW :)