Fix Elixir 1.16 warnings

- Fixes `Logger.warn` deprecation (requires bump to Elixir 1.11 which
  was released on 2020-10-06)
- ssl_verify_fun 1.1.6 doesn't compile under Elixir 1.16
- Remove `applications` definition and instead only use extra_applications
  - Fixes this warning "both :extra_applications and :applications was found in your mix.exs. You most likely want to remove the :applications key, as all applications are derived from your dependencies"
  - Also the applications listed in `apps` were just the normal
    dependencies (and logger)

lib/stripe/converter.ex

@@ -68,7 +68,7 @@ defmodule Stripe.Converter do
     defp warn_unknown_object(%{"object" => object_name}) do
       require Logger
 
-      Logger.warn("Unknown object received: #{object_name}")
+      Logger.warning("Unknown object received: #{object_name}")
     end
   end
 
@@ -103,7 +103,7 @@ defmodule Stripe.Converter do
 
         details = "#{module_name}: #{inspect(extra_keys)}"
         message = "Extra keys were received but ignored when converting #{details}"
-        Logger.warn(message)
+        Logger.warning(message)
       end
 
       :ok

lib/stripe/util.ex

@@ -85,7 +85,7 @@ defmodule Stripe.Util do
 
       quote bind_quoted: [mod: mod, fun: fun, arity: arity, msg: msg] do
         require Logger
-        Logger.warn("[DEPRECATION] The function #{mod}.#{fun}/#{arity} is deprecated. #{msg}")
+        Logger.warning("[DEPRECATION] The function #{mod}.#{fun}/#{arity} is deprecated. #{msg}")
       end
     end
   end

mix.exs

@@ -8,7 +8,7 @@ defmodule Stripe.Mixfile do
     [
       app: :stripity_stripe,
       version: @version,
-      elixir: "~> 1.10",
+      elixir: "~> 1.11",
       deps: deps(),
       docs: docs(),
       package: package(),
@@ -30,8 +30,7 @@ defmodule Stripe.Mixfile do
   # Configuration for the OTP application
   def application do
     [
-      applications: apps(Mix.env()),
-      extra_applications: [:plug],
+      extra_applications: [:logger],
       env: env(),
       mod: {Stripe, []}
     ]
@@ -53,10 +52,6 @@ defmodule Stripe.Mixfile do
     ]
   end
 
-  defp apps(:test), do: apps()
-  defp apps(_), do: apps()
-  defp apps, do: [:hackney, :logger, :jason, :uri_query]
-
   defp deps do
     [
       {:dialyxir, "1.1.0", only: [:dev, :test], runtime: false},

mix.lock

@@ -23,7 +23,7 @@
   "parse_trans": {:hex, :parse_trans, "3.3.1", "16328ab840cc09919bd10dab29e431da3af9e9e7e7e6f0089dd5a2d2820011d8", [:rebar3], [], "hexpm", "07cd9577885f56362d414e8c4c4e6bdf10d43a8767abb92d24cbe8b24c54888b"},
   "plug": {:hex, :plug, "1.14.0", "ba4f558468f69cbd9f6b356d25443d0b796fbdc887e03fa89001384a9cac638f", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:plug_crypto, "~> 1.1.1 or ~> 1.2", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4.3 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "bf020432c7d4feb7b3af16a0c2701455cbbbb95e5b6866132cb09eb0c29adc14"},
   "plug_crypto": {:hex, :plug_crypto, "1.2.3", "8f77d13aeb32bfd9e654cb68f0af517b371fb34c56c9f2b58fe3df1235c1251a", [:mix], [], "hexpm", "b5672099c6ad5c202c45f5a403f21a3411247f164e4a8fab056e5cd8a290f4a2"},
-  "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.6", "cf344f5692c82d2cd7554f5ec8fd961548d4fd09e7d22f5b62482e5aeaebd4b0", [:make, :mix, :rebar3], [], "hexpm", "bdb0d2471f453c88ff3908e7686f86f9be327d065cc1ec16fa4540197ea04680"},
+  "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.7", "354c321cf377240c7b8716899e182ce4890c5938111a1296add3ec74cf1715df", [:make, :mix, :rebar3], [], "hexpm", "fe4c190e8f37401d30167c8c405eda19469f34577987c76dde613e838bbc67f8"},
   "telemetry": {:hex, :telemetry, "1.1.0", "a589817034a27eab11144ad24d5c0f9fab1f58173274b1e9bae7074af9cbee51", [:rebar3], [], "hexpm", "b727b2a1f75614774cff2d7565b64d0dfa5bd52ba517f16543e6fc7efcc0df48"},
   "unicode_util_compat": {:hex, :unicode_util_compat, "0.7.0", "bc84380c9ab48177092f43ac89e4dfa2c6d62b40b8bd132b1059ecc7232f9a78", [:rebar3], [], "hexpm", "25eee6d67df61960cf6a794239566599b09e17e668d3700247bc498638152521"},
   "uri_query": {:hex, :uri_query, "0.1.2", "ae35b83b472f3568c2c159eee3f3ccf585375d8a94fb5382db1ea3589e75c3b4", [:mix], [], "hexpm", "e3bc81816c98502c36498b9b2f239b89c71ce5eadfff7ceb2d6c0a2e6ae2ea0c"},