pcb rev A3
- fixed the inconsistent and excessive brightness of the led indicators (D2, D3)
- fixed a bug where the VBUS indicator led (D2) can be dimly lit without VBUS being connected
- changed J1 from UJ2-ADH-W1-TH to the compatible USB-U267-BWS due to stock shortage
- cleaned up unused kicad libraries, and checked in libraries that were missing from the repo