Bump recommended PHP version to 8.1, min recommendation to 8.0

[colemanw]

Overview

According to php.net supported versions, 7.4 is already EOL and 8.0 will be EOL in 3 months.

Technical Details

This changes the recommendations but not the requirements for CiviCRM to run. Hopefully these notices encourage people to upgrade in a timely fashion.

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[colemanw]

Test this please

[wmortada]

It would be good to update the PHP version table in the documentation as this is quite out of date now.

See: https://lab.civicrm.org/documentation/docs/installation/-/issues/18

[seamuslee001]

going to merge this now that the RC has been cut

[jofranz]

@colemanw How does this affect PHP version recommendations?

[colemanw]

@jofranz the information on that page appears accurate to me. Do you see anything that needs updating?