treewide: add missing lib inputs

This fixes hopefully all remaining missing lib inputs, likely introduced
as a regression by our recent treewide switch from stdenv.lib to lib.
These instances are all I could find using nix-instantiate --parse using
the following command:

    find "$NIXPKGS" -name '*.nix' \
      -and ! -path "$NIXPKGS/pkgs/development/interpreters/python/cpython/docs/template.nix" \
      -and ! -path '$NIXPKGS/.git/**' \
      -print0 | xargs -0 nix-instantiate --parse >/dev/null

pkgs/tools/audio/beets/plugins/alternatives.nix

@@ -1,4 +1,4 @@
-{ fetchFromGitHub, beets, pythonPackages }:
+{ lib, fetchFromGitHub, beets, pythonPackages }:
 
 pythonPackages.buildPythonApplication rec {
   pname = "beets-alternatives";

pkgs/tools/audio/beets/plugins/copyartifacts.nix

@@ -1,4 +1,4 @@
-{ fetchFromGitHub, beets, pythonPackages, glibcLocales }:
+{ lib, fetchFromGitHub, beets, pythonPackages, glibcLocales }:
 
 pythonPackages.buildPythonApplication {
   name = "beets-copyartifacts";