Define base64url dependency only when using rebar2 and Erlang<24

base64url is not called directly in ejabberd code since e227940,
it is only required by p1_acme and erlang-jose 1.11.1

erlang-jose 1.11.1 defines base64url dependency as an hex package,
and rebar2 is not able to download it.
For that reason, when compiling ejabberd with rebar2,
we provide a rebar2-friendly base64url dependency definition.
That way when jose is downloaded, that dependency is already available.

.github/workflows/runtime.yml

@@ -193,7 +193,7 @@ jobs:
       run: |
         sed -i "s|^modules:|modules:\n  'ModPresenceDemo': {}|g" ejabberd.yml.example
         cat ejabberd.yml.example
-        sed -i 's|^{deps, \(.*\)|{deps, \1\n  {decimal, ".*", {git, "https://github.com/ericmj/decimal", {branch, "main"}}}, |g' rebar.config
+        sed -i 's|^{deps, \[\(.*\)|{deps, [{decimal, ".*", {git, "https://github.com/ericmj/decimal", {branch, "main"}}},\n \1|g' rebar.config
         cat rebar.config
 
     - name: Compile

mix.exs

@@ -44,7 +44,7 @@ defmodule Ejabberd.MixProject do
   def application do
     [mod: {:ejabberd_app, []},
      applications: [:idna, :inets, :kernel, :sasl, :ssl, :stdlib, :mix,
-                    :base64url, :fast_tls, :fast_xml, :fast_yaml, :jiffy, :jose,
+                    :fast_tls, :fast_xml, :fast_yaml, :jiffy, :jose,
                     :p1_utils, :stringprep, :syntax_tools, :yconf]
      ++ cond_apps(),
      included_applications: [:mnesia, :os_mon,
@@ -129,8 +129,7 @@ defmodule Ejabberd.MixProject do
   end
 
   defp deps do
-    [{:base64url, "~> 1.0"},
-     {:cache_tab, "~> 1.0"},
+    [{:cache_tab, "~> 1.0"},
      {:dialyxir, "~> 1.2", only: [:test], runtime: false},
      {:eimp, "~> 1.0"},
      {:ex_doc, "~> 0.31", only: [:dev, :edoc], runtime: false},

rebar.config

@@ -22,7 +22,10 @@
 %%% Dependencies
 %%%
 
-{deps, [{base64url, ".*", {git, "https://github.com/dvv/base64url", {tag, "1.0.1"}}},
+{deps, [{if_not_rebar3,
+         {if_version_below, "24",
+          {base64url, ".*", {git, "https://github.com/dvv/base64url", {tag, "1.0.1"}}}
+        }},
         {cache_tab, ".*", {git, "https://github.com/processone/cache_tab", {tag, "1.0.30"}}},
         {eimp, ".*", {git, "https://github.com/processone/eimp", {tag, "1.0.22"}}},
         {if_var_true, pam,