Modify namespace of ActiveRecord explain class

Ref: rails/rails#55736

Author: aidanharan

lib/active_record/connection_adapters/sqlserver/core_ext/explain_subscriber.rb

@@ -5,6 +5,6 @@
 ActiveSupport.on_load(:active_record) do
   silence_warnings do
     # Already defined in Rails
-    ActiveRecord::ExplainSubscriber::EXPLAINED_SQLS = /(select|update|delete|insert)\b/i
+    ActiveRecord::ExplainRegistry::Subscriber::EXPLAINED_SQLS = /(select|update|delete|insert)\b/i
   end
 end