HelpSpot 4.8.17

Enhancements
- A new command "php hs spam:clean" was added to help reduce size of the spam filter without reducing spam filtering quality
- Caching implemented on high-volume database queries, especially filter counts, to help on installs with a large number of filters. This reduces the load on the database server and improves admin page load times.
- Session garbage collection enhancement to remove old session data, especially for installs with high API usage
- Made improvements to spam filtering performance.
- Optimized tasks2 maintenance tasks to run once per day