* Adds the Elastic Endpoint and External Alerts rules and required schema updates
* Optimizing queries to fix tests
* Apply PEP257 changes
* Apply suggestions from code review
* Update rules/cross-platform/external_alerts.toml
* Last fixes from review
* Fixing test for unrequired default
* Adding increased default max_signals to not interfere with testing
* Make promotions folder
* Refining Elastic Endpoint rule index
Co-authored-by: Ross Wolf <31489089+rw-access@users.noreply.github.com>
Co-authored-by: Justin Ibarra <brokensound77@users.noreply.github.com>