Remove old code for php versions we no longer support

[ihor-sviziev]

In #39202, we did some cleanup, but it cleaned not all places.

It would be great to clean also

• checks for PHP < 8.1 https://github.com/search?q=repo%3Amagento%2Fmagento2%20PHP_VERSION&type=code
• hhvm-related things (AFAIK it's not supported for a long time) https://github.com/search?q=repo%3Amagento%2Fmagento2%20hhvm&type=code

Originally posted by @ihor-sviziev in #39202 (comment)

[m2-assistant]

Hi @ihor-sviziev. Thank you for your report.
To speed up processing of this issue, make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce.

• For more details, review the Magento Contributor Assistant documentation.
• Add a comment to assign the issue: @magento I am working on this
• To learn more about issue processing workflow, refer to the Code Contributions.

---

Join Magento Community Engineering Slack and ask your questions in #github channel.
⚠️ According to the Magento Contribution requirements, all issues must go through the Community Contributions Triage process. Community Contributions Triage is a public meeting.
🕙 You can find the schedule on the Magento Community Calendar page.
📞 The triage of issues happens in the queue order. If you want to speed up the delivery of your contribution, join the Community Contributions Triage session to discuss the appropriate ticket.

[m2-assistant]

Hi @engcom-Hotel. Thank you for working on this issue.
In order to make sure that issue has enough information and ready for development, please read and check the following instruction: 👇

• 1. Verify that issue has all the required information. (Preconditions, Steps to reproduce, Expected result, Actual result).
• 2. Verify that issue has a meaningful description and provides enough information to reproduce the issue.
• 3. Add Area: XXXXX label to the ticket, indicating the functional areas it may be related to.
• 4. Verify that the issue is reproducible on 2.4-develop branch
  Details

  - If the issue is reproducible on 2.4-develop branch, please, add the label Reproduced on 2.4.x.
  - If the issue is not reproducible, add your comment that issue is not reproducible and close the issue and stop verification process here!
• 5. Add label Issue: Confirmed once verification is complete.
• 6. Make sure that automatic system confirms that report has been added to the backlog.

[engcom-Hotel]

Hello @ihor-sviziev,

Thanks for the report and collaboration!

We are confirming this issue for further processing.

Thanks

[github-jira-sync-bot]

✅ Jira issue https://jira.corp.adobe.com/browse/AC-13349 is successfully created for this GitHub issue.

[m2-assistant]

✅ Confirmed by @engcom-Hotel. Thank you for verifying the issue.
Issue Available: @engcom-Hotel, You will be automatically unassigned. Contributors/Maintainers can claim this issue to continue. To reclaim and continue work, reassign the ticket to yourself.

[ihor-sviziev]

I also noticed that we have some workarounds for bugs in PHP itself: https://github.com/search?q=repo%3Amagento%2Fmagento2%20bugs.php.net&type=code
Maybe worth fixing them as well