[itsyBitsy nRF52840 express] changing the pixel value of `DotStar` instance only works when the board has been booted when USB connected

As said in the title, changing the color of the DostStar single pixel only works if the board boots (even just soft reboot) when the board is plugged to a USB host. As long as a power source remains, the USB can then be unplugged, the DotStar will behave as expected, until the next power on of the board

However, when booting from battery, while there is no crash, the DotStar do not react at all and remains lit off. Only crashes and other various error codes will still activate correctly the DotStar.

I don't think this is related to the mentioned issue, but I mention it just in case : I updated the bios and circuitPython just before testing for the first time your module. And I noticed a change in the DotStar behavior : before the update, the DotStar remained lit with a light green signifying it's running state. Now it remains off. Must be for energy saving reason.

No source file or test is identified in the report. Reproduce the DotStar pixel behavior on an ItsyBitsy nRF52840 Express when booted from USB versus battery, then trace the DotStar startup path; done means changing the pixel color works after a battery boot without crashes.

Written by the indexing model from the issue text.