Remove thread cleaner from Msf::Simple::Framework shared context

MSP-11605

The `framework` from 'Msf::Simple::Framework' shared context is not
guaranteed to make threads with `framework.threads` anymore, so the
cleaner shouldn't allows be present in 'Msf::Simple::Framework'.

Author: limhoff-r7

spec/support/shared/contexts/msf/simple/framework.rb

@@ -3,8 +3,6 @@
 require 'metasploit/framework'
 
 shared_context 'Msf::Simple::Framework' do
-  include_context 'Msf::Framework#threads cleaner'
-
   let(:dummy_pathname) do
     Rails.root.join('spec', 'dummy')
   end