Ensure correct PHP version is set
Ensure correct PHP version is set

Background: https://github.com/roots/trellis/issues/1354

https://github.com/roots/trellis/pull/1355 fixed half of this problem,
but there's still situations where php-cli ends up defaulting to 8.1.

This ensures the correct version of PHP is always set based on
`php_version` by using the `update-alternatives` command.

roots/trellis,roots/trellis,pressbooks/trellis,roots/bedrock-ansible,pressbooks/trellis,roots/bedrock-ansible