message: Update shell.nix to use current stable version.
diff: {pkgs ? import (builtins.fetchTarball {
  # Descriptive name to make the store path easier to identify
  - name = "nixos-2021-05";
  + name = "nixos-2021-11";
  # Commit hash
  - url = "https://github.com/NixOS/nixpkgs/archive/refs/tags/21.05.tar.gz";
  + url = "https://github.com/NixOS/nixpkgs/archive/refs/tags/21.11.tar.gz";
  # Hash obtained using `nix-prefetch-url --unpack <url>`
  - sha256 = "1ckzhh24mgz6jd1xhfgx0i9mijk6xjqxwsshnvq789xsavrmsc36";
  + sha256 = "162dywda2dvfj1248afxc45kcrg83appjd0nmdb541hl7rnncf02";
  }) {}}:
  pkgs.mkShell {
  buildInputs = with pkgs;
  [
  - git
  + bash
  bazel
  gcc
  + git
  glibc
  jdk
  python3
  