Include Thread status when printing leaked threads

MSP-11147

Sometime travis-ci is showing leaked threads even when
'Msf::Framework#threads cleaner' is being used, so I'm adding the
`Thread#status` to the data printed about the Thread to see if the
sometimes leaked threads have an odd status.  There's still a chance
that there will be a race-condition between when I call Thread.list and
I ask for each Thread's status that the VM could finish aborting a
Thread so that status I print isn't the same as the one that caused the
Thread to be returned in Thread.list.

lib/metasploit/framework/spec/threads/suite.rb

@@ -77,14 +77,18 @@ module Metasploit
                     if LOG_PATHNAME.exist?
                       caller_by_thread_uuid = Metasploit::Framework::Spec::Threads::Suite.caller_by_thread_uuid
 
-                      thread_uuids = thread_list.map { |thread|
-                        thread[Metasploit::Framework::Spec::Threads::Suite::UUID_THREAD_LOCAL_VARIABLE]
-                      }.compact
+                      thread_list.each do |thread|
+                        thread_uuid = thread[Metasploit::Framework::Spec::Threads::Suite::UUID_THREAD_LOCAL_VARIABLE]
+
+                        # unmanaged thread, such as the main VM thread
+                        unless thread_uuid
+                          next
+                        end
 
-                      thread_uuids.each do |thread_uuid|
                         caller = caller_by_thread_uuid[thread_uuid]
 
-                        error_lines << "Thread #{thread_uuid}\n"
+                        error_lines << "Thread #{thread_uuid}'s status is #{thread.status.inspect} " \
+                                       "and was started here:\n"
 
                         error_lines.concat(caller)
                       end