Test suite failing

[joerodrig]

Attempted to run the test suite on the following ruby versions: 2.4.10, 2.6.6 and 2.7.2

When running the test suite via rake test I get the following error on every API request:

API helpers: validate post callbacks#test_0001_can validate a verify callback:
Sailthru::ClientError: Unable to open stream to http://api.sailthru.com/send?api_key=my_api_key&format=json&json=%7B%22send_id%22%3A%22TT1ClGdj2bRHAAP6%22%7D&sig=7a2ec442f410f7c5c118c469e3dcf0b0: undefined method `close' for #<FakeWeb::StubSocket:0x00007ff384026e38>
Did you mean?  closed?
               clone
    ./sailthru-ruby-client/lib/sailthru/client.rb:899:in `rescue in http_request'
    my-path/sailthru-ruby-client/lib/sailthru/client.rb:879:in `http_request'
    my-path/sailthru-ruby-client/lib/sailthru/client.rb:809:in `api_request'
    my-path/sailthru-ruby-client/lib/sailthru/client.rb:753:in `api_get'
    my-path/sailthru-ruby-client/lib/sailthru/client.rb:73:in `get_send'
    my-path/sailthru-ruby-client/lib/sailthru/client.rb:295:in `receive_verify_post'
    my-path/sailthru-ruby-client/test/sailthru/receive_post_callback_test.rb:27:in `block (2 levels) in <class:ReceivePostCallbackTest>'

It seems like it's due to the use of the FakeWeb gem which hasn't been updated in about 10 years and seems to have a <= 2.3 requirement for Ruby. Are there any plans to remove this gem as a dependency and use something like Webmock? Is this something that any maintainers on this project are open to?

Related issue: chrisk/fakeweb#62