Rebar/Rebar3: Update binaries to work with Erlang/OTP 24-27

They are compiled from their git repositories, main branches,
using erlang:24-slim docker image.

To compile ejabberd using rebar/rebar3 and Erlang 20.0 up to 23.3,
you can download the old binaries from ejabberd 21.12, available at:
  https://github.com/processone/ejabberd/raw/21.12/rebar
  https://github.com/processone/ejabberd/raw/21.12/rebar3