Update ubuntu amis in amis.yaml

@yas, please review this patch. This fixes the following:

• Updating AMIs to Ubuntu 24.04LTS.
• Updating UserData to fix pip install for cfnsignal
• Removing need to explicitly declare PHP 8.3. PHP 8.3 is the default version for Ubuntu 24.04LTS
• Adding assert.active = Off to Dockerfile. assert.active is deprecated and can return a PHP warning. This shows up during a Drupal cache clear.

@baldwinlouie

Thank you for the MR. I’ll merge the patch into 8.x; and close this issue as Fixed.