Require 'date' to avoid retry exception

[rustygeldmacher]

Without requiring 'date', we get an exception in the retry middleware
when it tries to use DateTime for handling the Retry-After header.

Description

This simple script can be used to reproduce the bug:

#!/usr/bin/env ruby

require 'faraday'

conn = Faraday.new('https://amazon.com') do |f|
  f.request :retry, {
    retry_statuses: [301],
    max: 1,
    interval: 1.0,
    backoff_factor: 2
  }
end

conn.get('gp/css/order-history')

The fix is to simply add a require for Ruby's date library so we don't get an exception during retries.

I'm not certain this warrants a spec change (or if that'd even be possible?) but please let me know!

[olleolleolle]

Thanks for the repair!

@rustygeldmacher Awesome!

[olleolleolle]

Awesome, @rustygeldmacher - thanks!

[iMacTia]

OMG just realised this was already fixed in #844 but only in 0.1x because of the mess we were in at the time to get v1.0 done 🙈
Thanks @rustygeldmacher 🎉