[Backport] Allow to read HTTP/2 response header.

[gelanivishal]

Original Pull Request

#19143

This change fixes ability to read response from third-party servers that use HTTP/2 if your server use HTTP/2 too.

Description

The issue is HTTP/2 sends the following headers HTTP/2 200, HTTP/2 401 and so on. It doesn't have third parameter like HTTP/1.1 has: HTTP/2 200 OK

Fixed Issues

1. Cannot connect to Magento 2 market place #19127: Cannot connect to Magento 2 market place

Manual testing scenarios

1. Enable HTTP/2 on your server
2. Try to login to marketplace from System > Web Setup Wizard. You can use invalid credentials too.
3. You will see a message about invalid response line instead of "Bad Credentials" message.

Contribution checklist (*)

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[magento-engcom-team]

Hi @gelanivishal. Thank you for your contribution
Here is some useful tips how you can test your changes using Magento test environment.
Add the comment under your pull request to deploy test or vanilla Magento instance:

• @magento-engcom-team give me test instance - deploy test instance based on PR changes
• @magento-engcom-team give me 2.2-develop instance - deploy vanilla Magento instance

For more details, please, review the Magento Contributor Assistant documentation

[magento-engcom-team]

Hi @orlangur, thank you for the review.
ENGCOM-3479 has been created to process this Pull Request

[magento-engcom-team]

Hi @gelanivishal. Thank you for your contribution.
We will aim to release these changes as part of 2.2.8.
Please check the release notes for final confirmation.

Please, consider to port this solution to 2.3 release line.
You may use Porting tool to port commits automatically.