docs: Prepare Changelog for 6.8.13 (#22072)

* docs: Close changelog for 6.8.13

* Apply suggestions from code review

Co-authored-by: kuisathaverat <kuisathaverat@gmail.com>
Co-authored-by: Ivan Fernandez Calvo <kuisathaverat@users.noreply.github.com>

CHANGELOG.asciidoc

@@ -3,6 +3,17 @@
 :issue: https://github.com/elastic/beats/issues/
 :pull: https://github.com/elastic/beats/pull/
 
+[[release-notes-6.8.13]]
+=== Beats version 6.8.13
+https://github.com/elastic/beats/compare/v6.8.12...v6.8.13[View commits]
+
+==== Added
+
+*Filebeat*
+
+- Add container image in Kubernetes metadata {pull}13356[13356] {issue}12688[12688]
+
+
 [[release-notes-6.8.12]]
 === Beats version 6.8.12
 https://github.com/elastic/beats/compare/v6.8.11...v6.8.12[View commits]

CHANGELOG.next.asciidoc

@@ -59,7 +59,6 @@ https://github.com/elastic/beats/compare/v6.8.0...6.8.1[Check the HEAD diff]
 
 *Filebeat*
 
-- Add container image in Kubernetes metadata {pull}13356[13356] {issue}12688[12688]
 
 *Heartbeat*
 

libbeat/docs/release.asciidoc

@@ -8,6 +8,7 @@ This section summarizes the changes in each release. Also read
 <<breaking-changes>> for more detail about changes that affect
 upgrade.
 
+* <<release-notes-6.8.13>>
 * <<release-notes-6.8.12>>
 * <<release-notes-6.8.11>>
 * <<release-notes-6.8.10>>