Incompatible with WebMock 3.16.0

[jdufresne]

WebMock recently had a new release 3.16.0. This causes issues when used with Active Merchant due to it accessing private instance variables. See here:

active_merchant/lib/active_merchant/net_http_ssl_connection.rb

Lines 6 to 8 in 3407c02

	return {} unless use_ssl? && @socket.present?
	{ version: @socket.io.ssl_version, cipher: @socket.io.cipher[0] }

On at least one occasion, Active Merchant has made changes to remain compatible with WebMock, so it seems like the current situation is not desirable. See: #2874.

The issue was tracked down to WebMock PR bblimke/webmock#976.

Below is an example script that shows the incompatibility. This script does not fail with WebMock 3.15.

require 'activemerchant'
require 'webmock'
include WebMock::API

WebMock.enable!

stub_request(:post, "https://api2.authorize.net/xml/v1/request.api")

ActiveMerchant::Billing::Base.mode = 'test'

credit_card = ActiveMerchant::Billing::CreditCard.new({
  number: '4111111111111111',
  month: '11',
  year: '25',
  first_name: 'John',
  last_name: 'Doe',
  verification_value: '111',
})

gateway = ActiveMerchant::Billing::AuthorizeNetGateway.new(
  login: 'test',
  password: 'test',
)

gateway.authorize(1000, credit_card)

/home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/net_http_ssl_connection.rb:8:in `ssl_connection': undefined method `ssl_version' for #<StubSocket::StubIO:0x00007f222d331f48> (NoMethodError)

      { version: @socket.io.ssl_version, cipher: @socket.io.cipher[0] }
                           ^^^^^^^^^^^^
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/connection.rb:82:in `block (2 levels) in request'
	from /home/jon/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/benchmark.rb:311:in `realtime'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/connection.rb:80:in `block in request'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/network_connection_retries.rb:24:in `block in retry_exceptions'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/network_connection_retries.rb:52:in `retry_network_exceptions'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/network_connection_retries.rb:23:in `retry_exceptions'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/connection.rb:75:in `request'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/posts_data.rb:74:in `raw_ssl_request'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/posts_data.rb:44:in `ssl_request'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/posts_data.rb:40:in `ssl_post'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/billing/gateways/authorize_net.rb:817:in `commit'
	from /home/jon/test-webmock/.bundle/ruby/3.1.0/gems/activemerchant-1.126.0/lib/active_merchant/billing/gateways/authorize_net.rb:120:in `authorize'
	from test.rb:27:in `<main>'

[github-actions]

To provide a cleaner slate for the maintenance of the library, this PR/Issue is being labeled stale after 60 days without activity. It will be closed in 14 days unless you comment with an update regarding its applicability to the current build. Thank you!