Fix deprecation by avoiding a deprecation on the name method

Fixes the warning:

DEPRECATION WARNING: ActiveSupport::TimeWithZone.name has been deprecated and
from Rails 7.1 will use the default Ruby implementation.
You can set `config.active_support.remove_deprecated_time_with_zone_name = true`
to enable the new behavior now.
 (called from block in ruby_object_usage at /Users/joerafaniello/Code/manageiq/app/models/miq_worker/runner.rb:435)

app/models/miq_worker/runner.rb

@@ -436,7 +436,7 @@ def self.ruby_object_usage
     ObjectSpace.each_object(Object) do |obj|
       next unless defined?(obj.class)
 
-      types[obj.class.name] += 1
+      types[obj.class.to_s] += 1
     end
     types
   end