chore(flake): 🥐 update lockfile

[cratelyn]

describe your changes

this updates the flake.lock lockfile, via running nix flake update.

issue ticket number and link

n/a

checklist before requesting a review

• if this code contains consensus-breaking changes, i have added the
  "consensus-breaking" label. otherwise, i declare my belief that there are not
  consensus-breaking changes, for the following reason:

  this is only a change to developer tooling, specifically, a lockfile
  recording the versions of e.g. nixpkgs in use in the development shell.