Context

Support team often get question around "How do I manually close connection" with PHP driver. 

Expected

• Update FAQs to include this answer - Unlike legacy driver, current PHP driver doesn't not provide any explicit method to close connection. 
• Add the rationale (WHY), resources (like documentation on connection handling in PHP) and guidance.
  • https://github.com/mongodb/mongo-php-library/blob/master/docs/faq.txt
  • https://www.mongodb.com/docs/php-library/current/faq/