All lens deletion bug

[Hissssst]

As @ffloyd mentioned in #20, I see some weird behavior with all/0 lens:

import Pathex

data = [
  %{ "a" => 1 },
  %{ "a" => 2 }
]

all_a = Pathex.Lenses.all() ~> path("a")

Pathex.get(data, all_a) |> IO.inspect(label: "get")
Pathex.delete!(data, all_a) |> IO.inspect(label: "delete!")

And as result get/2 works, but delete/2 fails:

** (Pathex.Error) 
  Couldn't find element

    Path:      all() ~> path("a")

    Structure: [%{"a" => 1}, %{"a" => 2}]

    (stdlib 3.17.2) erl_eval.erl:685: :erl_eval.do_apply/6
    (stdlib 3.17.2) erl_eval.erl:893: :erl_eval.expr_list/6
    (stdlib 3.17.2) erl_eval.erl:408: :erl_eval.expr/5
    (elixir 1.14.0) lib/module/parallel_checker.ex:100: Module.ParallelChecker.verify/1

[Hissssst]

Fixed in v2.4.2