[DOCS] Omitted security PR from release notes
Original commit: elastic/x-pack-elasticsearch@62229dad45194cde1e36ef101bafa47baf719f2c
@@ -17,9 +17,3 @@ Security::
environment file.
//Repo: x-pack-elasticsearch
//Pull: 3848
-* If the realm uses native role mappings and the security index health changes,
-the realm caches are cleared. For example, they are cleared when the index
-recovers from a red state, when the index is deleted, when the index becomes
-outdated, or when the index becomes up-to-date.
-//Repo: x-pack-elasticsearch
-//Pull: 3782
