Add LED_WS2812B-Mini_PLCC4_3.5x3.5mm

Here's the submission of the 3D model of WS2812B-Mini generated from the script corresponding to the linked merge request.

See also:

• kicad-packages3D-generator!35 (merged) for the 3D model source
• kicad-footprints!2899 (merged) for the footprint

• A screenshot of the model(s) aligned with KiCad footprint(s)
• Source files are contributed on the appropriate location
• Step model submitted in 1:1 scale
• WRL model submitted in 1:2.54 scale
• 3D model alignment checked against KiCad footprint
• WRL model uses correct material properties
• Geometry check performed on the model

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