[apfbug] beta 3 (for Tiliqua R2/R3)

What's Changed

• Make sure to flash the correct .uf2 for your hardware revision to the RP2040.
• Adds a workaround for #2 - (WARN: CDC/UART is now stuck at 115200 and ignores line state changes!)
• cdc_uart: (workaround) fix spurious enumeration failure after re-plug by @vk2seb in #5
• descriptors: generate USB product string from git tag by @vk2seb in #6

Full Changelog: beta0...apfbug-beta3