Add release notes and highlights for 2.12.1 (#7667) (#7670)

---------
Co-authored-by: Michael Montgomery <[email protected]>

Author: thbkrkr

docs/release-notes.asciidoc

@@ -6,6 +6,7 @@
 
 This section summarizes the changes in each release.
 
+* <<release-notes-2.12.1>>
 * <<release-notes-2.12.0>>
 * <<release-notes-2.11.1>>
 * <<release-notes-2.11.0>>
@@ -46,6 +47,7 @@ This section summarizes the changes in each release.
 
 --
 
+include::release-notes/2.12.1.asciidoc[]
 include::release-notes/2.12.0.asciidoc[]
 include::release-notes/2.11.1.asciidoc[]
 include::release-notes/2.11.0.asciidoc[]

docs/release-notes/2.12.1.asciidoc

@@ -0,0 +1,12 @@
+:issue: https://github.com/elastic/cloud-on-k8s/issues/
+:pull: https://github.com/elastic/cloud-on-k8s/pull/
+
+[[release-notes-2.12.1]]
+== {n} version 2.12.1
+
+
+[[bug-2.12.1]]
+[float]
+=== Bug fixes
+
+* Move desired nodes version gate in the client {pull}7663[#7663] (issue: {issue}7664[#7664])

docs/release-notes/highlights-2.12.1.asciidoc

@@ -0,0 +1,12 @@
+[[release-highlights-2.12.1]]
+== 2.12.1 release highlights
+
+This is a patch release to address some issues found after the 2.12.0 release. Check <<release-highlights-2.12.0>> for the full highlights of the 2.12.x series.
+
+[float]
+[id="{p}-2121-new-and-notable"]
+=== Bug fix
+
+This release fixes an issue where the operator may encounter a stall during the upgrade of Elasticsearch to version 8.13.0.
+
+Also refer to <<{p}-2120-known-issue>> for more information.

docs/release-notes/highlights.asciidoc

@@ -5,6 +5,7 @@
 --
 This section summarizes the most important changes in each release. For the full list, check <<eck-release-notes>>.
 
+* <<release-highlights-2.12.1>>
 * <<release-highlights-2.12.0>>
 * <<release-highlights-2.11.1>>
 * <<release-highlights-2.11.0>>
@@ -45,6 +46,7 @@ This section summarizes the most important changes in each release. For the full
 
 --
 
+include::highlights-2.12.1.asciidoc[]
 include::highlights-2.12.0.asciidoc[]
 include::highlights-2.11.1.asciidoc[]
 include::highlights-2.11.0.asciidoc[]