flake.lock: Update

Flake lock file updates:

• Updated input 'flake-compat':
    'github:edolstra/flake-compat/b7547d3eed6f32d06102ead8991ec52ab0a4f1a7' (2022-01-03)
  → 'github:edolstra/flake-compat/64a525ee38886ab9028e6f61790de0832aa3ef03' (2022-03-25)
• Updated input 'flake-utils':
    'github:numtide/flake-utils/3cecb5b042f7f209c56ffd8371b2711a290ec797' (2022-02-07)
  → 'github:numtide/flake-utils/0f8662f1319ad6abf89b3380dd2722369fc51ade' (2022-03-26)
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/fcd48a5a0693f016a5c370460d0c2a8243b882dc' (2022-03-10)
  → 'github:nixos/nixpkgs/42948b300670223ca8286aaf916bc381f66a5313' (2022-04-08)
• Updated input 'rust-overlay':
    'github:oxalica/rust-overlay/c984623eb0584a2aadeca505dd85ec68a3f5a576' (2022-03-13)
  → 'github:oxalica/rust-overlay/4579190c4c427b8350c662417c26254589dfe658' (2022-04-09)

Author: github-actions[bot]