Add `php-compatibility` focus to Core's Trac to identify PHP incompatibility

[hellofromTonya]

Please add a php-compatibility focus to Core's Trac tickets in the "Contributor Focuses" section.

This new focus identifies an incompatibility with one or more specific PHP versions, such as PHP 8.2, 9.0, etc:

Add the php-compatibility focus with a description of “Relating to PHP forward and backwards compatibility. A phpNN keyword identifies the PHP version that introduced the incompatibility”.

phpNN where NN is the specific PHP version that introduced the incompatibility within WordPress Core. For example, if there's an incompatibility with PHP 8.2, then phpNN is php82.

It's part of a recently adopted proposal: ​Proposal: Criteria for Removing "Beta Support" from Each PHP 8+ Version.

[SergeyBiryukov]

In 12771:

Trac: Add a php-compatibility focus to core.trac.wordpress.org.

Props hellofromTonya.
Fixes #7169.

[SergeyBiryukov]

In 12777:

Trac: Bump scripts version after [12771].

See #7169.

Adds php-compatibility to the shortcode, which in turn makes this option available in the "Tickets by Focus" dropdown on the ​Trac reports page. Allows ticket reports with this focus to be more conveniently accessed.

Also see https://meta.trac.wordpress.org/ticket/7169, where this keyword was introduced.

[dd32]

In 13688:

Make: Trac: Sync the list of trac focuses.

Props ironprogrammer, dd32.
Closes ​https://github.com/WordPress/wordpress.org/pull/314
See #7169.