Update to Debian 11 and node 16

[mtoman]

The block is currently based on Debain 10, however its mesa version is too old for RPi kernel 5.15.9 and up which results in X server crashing on startup.

This patch updates the base to Debian 11 and bumps to node 16, which works on all architectures.

[jellyfish-bot]

[mtoman] This has attached https://jel.ly.fish/635382fa-59af-4138-b01c-29e9e0c725ea

[rcooke-warwick]

lgtm