Update the supported PHP versions

The PHP version table should be updated to include PHP 8.

This section is referenced in CiviCRM 5.39 Release Notes and elsewhere as showing that CiviCRM now supports PHP 8 but it isn't actually mentioned here.

I'll draft a change for this but would appreciate it if others could check it looks okay.

mentioned in commit 3829aab9

mentioned in merge request !33 (merged)

mentioned in commit 1cf76fdf

closed with commit 3829aab9

Sorry didn't see the followup message William :-)

No worries! You've saved me a job. Very quick work!!

Should we link to dev/core#2201 (closed) for more details on PHP compatibility?

I was going to - but there's no real detail there at the moment which seems relevant.