security_tracker: rate limit RSS feeds

Issue with RSS feeds observed in security.archlinux.org 05/04/2023. A few IPs were hitting the RSS feeds with high requests / second and managed to get the server down due to too many requests.

requested review from @foutrelis, @jelle, @klausenbusk, @anthraxx, and @svenstaro

assigned to @artafinde

approved this merge request

added 1 commit

• d49f74d4 - security_tracker: rate limit RSS feeds

Compare with previous version

This is deployed now.

mentioned in commit 2594598a

merged