remove a spurious require that triggers a circular require warning

mvidner · mvidner · commit 8ceb6344820e · 2025-04-03T14:28:21.000+02:00
warning: loading in progress, circular require considered harmful - .../rubygems.rb
diff --git a/ruby-dbus.gemspec b/ruby-dbus.gemspec
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 # -*- ruby -*-
-require "rubygems"
 
 GEMSPEC = Gem::Specification.new do |s|
   s.name = "ruby-dbus"
