Remove fiber HTTP test.

The HTTP test hits a remote website which isn't always available and is
not self-contained. Ideally we will rewrite this test with an internal
web server.

test/fiber/test_http.rb

@@ -1,28 +0,0 @@
-# frozen_string_literal: true
-
-require 'net/http'
-require 'uri'
-require 'openssl'
-
-require 'test/unit'
-require_relative 'scheduler'
-
-class TestFiberHTTP < Test::Unit::TestCase
-  def test_get
-    Thread.new do
-      scheduler = Scheduler.new
-      Thread.current.scheduler = scheduler
-
-      Fiber do
-        uri = URI("https://www.ruby-lang.org/en/")
-
-        http = Net::HTTP.new uri.host, uri.port
-        http.use_ssl = true
-        http.verify_mode = OpenSSL::SSL::VERIFY_NONE
-        body = http.get(uri.path).body
-
-        assert !body.empty?
-      end
-    end.join
-  end
-end