Add release notes for 1.3.2 (#3202)

Signed-off-by: Andrew Ross <andrross@amazon.com>

Author: andrross

release-notes/opensearch.release-notes-1.3.2.md

@@ -0,0 +1,16 @@
+## Version 1.3.2 Release Notes
+
+### Upgrades
+
+* Update bundled JDK to 11.0.15+10 ([#3134](https://github.com/opensearch-project/OpenSearch/pull/3134))
+* [CVE-2020-36518] Update jackson-databind to 2.12.6.1 ([#2706](https://github.com/opensearch-project/OpenSearch/pull/2706))
+
+### Enhancements
+
+* Use G1GC on JDK11+ ([#2971](https://github.com/opensearch-project/OpenSearch/pull/2971))
+
+### Infrastructure
+
+* Fix opensearch-env always sources the environment from hardcoded file ([#2909](https://github.com/opensearch-project/OpenSearch/pull/2909))
+* Backporting changes for version workflow ([#2676](https://github.com/opensearch-project/OpenSearch/pull/2676))
+* Bump the version to 1.3.2 ([#2675](https://github.com/opensearch-project/OpenSearch/pull/2675))