Remove outdated shell file

shell.nix

@@ -1,38 +0,0 @@
-{
-  pkgs ? import <nixpkgs-unstable> { },
-}:
-
-pkgs.mkShell rec {
-  name = "qois-infrastructure-shell";
-  buildInputs =
-    let
-      extensions = with pkgs.vscode-extensions; [ jnoortheen.nix-ide ];
-      vscode-with-extensions = pkgs.vscode-with-extensions.override { vscodeExtensions = extensions; };
-    in
-    with pkgs;
-    [
-      vscode-with-extensions
-      nixfmt
-      rnix-lsp
-    ];
-  LANG = "C.UTF-8";
-  LC_ALL = "C.UTF-8";
-  shellHook = ''
-    # Bring xdg data dirs of dependencies and current program into the
-    # environment. This will allow us to get shell completion if any
-    # and there might be other benefits as well.
-    xdg_inputs=( "''${buildInputs[@]}" )
-    for p in "''${xdg_inputs[@]}"; do
-      if [[ -d "$p/share" ]]; then
-        XDG_DATA_DIRS="''${XDG_DATA_DIRS}''${XDG_DATA_DIRS+:}$p/share"
-      fi
-    done
-    export XDG_DATA_DIRS
-
-    # Make sure we support the pure case as well as non nixos cases
-    # where dynamic bash completions were not sourced.
-    #if ! type _completion_loader > /dev/null; then
-    #  . ${pkgs.bash-completion}/etc/profile.d/bash_completion.sh
-    #fi
-  '';
-}