DEV-45: Prevent 404 in the-build-installer by updating acquia memcache install task

[jesconstantine]

User story: DEV-45: 404 error on install in request for Acquia memcache config file

Description

This PR updates the process for adding memcache to an acquia project based on https://docs.acquia.com/cloud-platform/performance/memcached/enable/#configuration-for-drupal-9-or-later

• Update the steps taken for acquia-hosted projects to add a composer dependency instead of making a HTTP request for an acquia-provided settings file per https://docs.acquia.com/cloud-platform/performance/memcached/enable/#configuration-for-drupal-9-or-later

Test Steps

Test in palantirnet/drupal-skeleton#149 which points to this branch in is composer.json for the-build

[becw]

I tested this using palantirnet/drupal-skeleton#149 and it did exactly what it says on the tin.