fix: Don't redefine builtin exception

This is to test my idea from
#176 (comment)
where I've said that I don't think this is necessary since the Elixir
stdlib for Exceptions already has this [1]?

[1] https://github.com/elixir-lang/elixir/blob/main/lib/elixir/lib/exception.ex#L807

lib/paginator/config.ex

@@ -20,10 +20,6 @@ defmodule Paginator.Config do
     :total_count_limit
   ]
 
-  defmodule ArgumentError do
-    defexception [:message]
-  end
-
   @default_total_count_primary_key_field :id
   @default_limit 50
   @minimum_limit 1
@@ -59,17 +55,17 @@ defmodule Paginator.Config do
 
   def validate!(%__MODULE__{} = config) do
     unless config.cursor_fields do
-      raise(Paginator.Config.ArgumentError, message: "expected `:cursor_fields` to be set")
+      raise(Paginator.ArgumentError, message: "expected `:cursor_fields` to be set")
     end
 
     if !cursor_values_match_cursor_fields?(config.after_values, config.cursor_fields) do
-      raise(Paginator.Config.ArgumentError,
+      raise(Paginator.ArgumentError,
         message: "expected `:after` cursor to match `:cursor_fields`"
       )
     end
 
     if !cursor_values_match_cursor_fields?(config.before_values, config.cursor_fields) do
-      raise(Paginator.Config.ArgumentError,
+      raise(Paginator.ArgumentError,
         message: "expected `:before` cursor to match `:cursor_fields`"
       )
     end

test/paginator/config_test.exs

@@ -120,15 +120,15 @@ defmodule Paginator.ConfigTest do
     test "raises ArgumentError when cursor_fields are not set" do
       config = Config.new([])
 
-      assert_raise Config.ArgumentError, "expected `:cursor_fields` to be set", fn ->
+      assert_raise ArgumentError, "expected `:cursor_fields` to be set", fn ->
         Config.validate!(config)
       end
     end
 
     test "raises ArgumentError when after cursor does not match the cursor_fields" do
       config = Config.new(cursor_fields: [:date], after: complex_after())
 
-      assert_raise Config.ArgumentError,
+      assert_raise ArgumentError,
                    "expected `:after` cursor to match `:cursor_fields`",
                    fn ->
                      Config.validate!(config)
@@ -146,7 +146,7 @@ defmodule Paginator.ConfigTest do
             })
         )
 
-      assert_raise Config.ArgumentError,
+      assert_raise ArgumentError,
                    "expected `:after` cursor to match `:cursor_fields`",
                    fn ->
                      Config.validate!(config)
@@ -170,7 +170,7 @@ defmodule Paginator.ConfigTest do
     test "raises ArgumentError when before cursor does not match the cursor_fields" do
       config = Config.new(cursor_fields: [:id], before: complex_before())
 
-      assert_raise Config.ArgumentError,
+      assert_raise ArgumentError,
                    "expected `:before` cursor to match `:cursor_fields`",
                    fn ->
                      Config.validate!(config)