[DOCS] Updates release notes for 8.12.2

Author: picandocodigo

CHANGELOG.md

@@ -1,5 +1,9 @@
 *To see release notes for the `7.x` branch and older releases, see [CHANGELOG on the 7.17 branch](https://github.com/elastic/elasticsearch-ruby/blob/7.17/CHANGELOG.md).*
 
+## 8.12.2 Release notes
+
+Drops runtime dependency on `base64`. Thanks [Earlopain](https://github.com/Earlopain)! Pull Request: [#2295](https://github.com/elastic/elasticsearch-ruby/pull/2295).
+
 ## 8.12.1 Release notes
 
 Adds `base64` dependency

docs/release_notes/812.asciidoc

@@ -1,6 +1,12 @@
 [[release_notes_8_12]]
 === 8.12 Release notes
 
+[discrete]
+[[release_notes_8_12_2]]
+=== 8.12.2 Release notes
+
+Drops runtime dependency on `base64`. Thanks https://github.com/Earlopain[Earlopain]! Pull Request: https://github.com/elastic/elasticsearch-ruby/pull/2295[#2295]).
+
 [discrete]
 [[release_notes_8_12_1]]
 === 8.12.1 Release notes