Update flake.lock

[simonrw]

Automated changes by the update-flake-lock GitHub Action.

Flake lock file updates:

• Updated input 'flake-utils':
    'github:numtide/flake-utils/4022d587cbbfd70fe950c1e2083a02621806a725' (2023-12-04)
  → 'github:numtide/flake-utils/1ef2e671c3b0c19053962c07dbda38332dcebf26' (2024-01-15)
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/bd645e8668ec6612439a9ee7e71f7eac4099d4f6' (2024-01-02)
  → 'github:nixos/nixpkgs/842d9d80cfd4560648c785f8a4e6f3b096790e19' (2024-01-17)

Running GitHub Actions on this PR

GitHub Actions will not run workflows on pull requests which are opened by a GitHub Action.

To run GitHub Actions workflows on this PR, run:

git branch -D update_flake_lock_action
git fetch origin
git checkout update_flake_lock_action
git commit --amend --no-edit
git push origin update_flake_lock_action --force

[coveralls]

coverage: 77.464%. remained the same
when pulling 5f3a9e3 on update_flake_lock_action
into 9aee2e0 on main.