Fix occasional update_cache idempotence failure

[alessfg]

Proposed changes

Using update_cache: true by itself in the apt module is not always idempotent. Moved the NGINX App Protect installation task to a corresponding apt or yum module to avoid this scenario.

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING document
• I have added Molecule tests that prove my fix is effective or that my feature works
• I have checked that all Molecule tests pass after adding my changes
• I have updated any relevant documentation (defaults/main.yml, README.md and CHANGELOG.md)