chore: update elixir verison, use new struct match

Author: zachdaniel

.tool-versions

@@ -1,3 +1,3 @@
-erlang 27.0.1
-elixir 1.18.4
+erlang 28.2
+elixir 1.19.3
 pipx 1.8.0

lib/ash_json_api/plug/parser.ex

@@ -145,11 +145,12 @@ defmodule AshJsonApi.Plug.Parser do
          false
        )
        when data == %{} do
+    %Plug.Conn{} = conn
     with {:ok, type, subtype, _params} <- extract_part_type(part_headers),
          {:ok, content} <- File.read(path),
          {:ok, data, conn} <-
            JSON.parse(
-             %Plug.Conn{conn | private: Map.put(conn.private, __MODULE__, content)},
+             %{conn | private: Map.put(conn.private, __MODULE__, content)},
              type,
              subtype,
              part_headers,