View Source PulsarEx.Backoff (PulsarEx v0.14.0)
adopted from db_connection https://github.com/elixir-ecto/db_connection/blob/v2.4.3/lib/db_connection/backoff.ex
adopted from db_connection https://github.com/elixir-ecto/db_connection/blob/v2.4.3/lib/db_connection/backoff.ex