changelog: add entry for 8.16.3 (#15188)

(cherry picked from commit a7bb6f9)

changelogs/8.16.asciidoc

@@ -1,10 +1,38 @@
 [[apm-release-notes-8.16]]
 == APM version 8.16
 
+* <<apm-release-notes-8.16.3>>
 * <<apm-release-notes-8.16.2>>
 * <<apm-release-notes-8.16.1>>
 * <<apm-release-notes-8.16.0>>
 
+[float]
+[[apm-release-notes-8.16.3]]
+=== APM version 8.16.3
+
+https://github.com/elastic/apm-server/compare/v8.16.2\...v8.16.3[View commits]
+
+[float]
+==== Bug fixes
+
+- Install APM Server in Program Files directory on Windows {pull}14905[14905]
+- Fix self instrumentation events inconsistency when dealing with request timeout {pull}15123[15123]
+- Drop and recreate tail-based sampling badger db after exceeding storage limit for configured TTL time {pull}15106[15106]
+
+[float]
+==== Breaking Changes
+
+[float]
+==== Deprecations
+
+[float]
+==== Intake API Changes
+
+[float]
+==== Added
+
+- Add sampling.tail.discard_on_write_failure config (default=false) to opt in to data loss when tail-based sampling storage limit is reached {pull}15159[15159]
+
 [float]
 [[apm-release-notes-8.16.2]]
 === APM version 8.16.2