Update Requests library

[jrf]

The Requests library has released a new version: 1.8.0.

A number of the fixes contained in this release are already in the WordPress Core copy of it via [38727], [46258], [47902] and [49382].

However, this release contains further improvements, including:

• A (significant) performance fix when using cURL
• An update to the bundled certificates
• Improved compliance with RFC2616
• and more

Full changelog: ​https://github.com/WordPress/Requests/releases/tag/v1.8.0
Website (updated): ​https://requests.ryanmccue.info/

It is recommended for WordPress to update the bundled version of Requests in the next release.

Previous: #33055, #47746, #49922

Trac ticket: https://core.trac.wordpress.org/ticket/53101

[desrosj]

In 50842:

External Libraries: Update the Requests library to version 1.8.0.

While some of the changes in the 1.8.0 release have already been copied to WordPress Core in earlier releases (see [38727], [46258], [47902] and [49382]), this release contains additional improvements, including:

• A significant performance fix when using cURL.
• Improved compliance with RFC2616.

The library has also been moved under the WordPress project’s GitHub organization and can now be found at ​https://github.com/WordPress/Requests.

Props jrf, dd32, rmccue, justinahinon, netweb, schlessera, TimothyBJacobs, soulseekah, ozh, skithund, carlalexander, travisnorthcutt, desrosj.
Fixes #53101.

[desrosj]

I matched up WordPress.org usernames for props as best I could for anyone mentioned in the release notes. There were a small handful I was unable to verify .org accounts for. If you were missed in the Props list above and contributed to Requests 1.8.0, feel free to leave a comment here and we'll make sure you're properly credited!

Merged into Core in https://core.trac.wordpress.org/changeset/50842.