[chore] Update CHANGELOG.md with 1.3.12 release (#4739)

Signed-off-by: Manasvini B Suryanarayana <manasvis@amazon.com>

CHANGELOG.md

@@ -69,6 +69,33 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ### 🔩 Tests
 
+## [1.3.12 - 2023-08-10](https://github.com/opensearch-project/OpenSearch-Dashboards/releases/tag/1.3.12)
+
+### 🛡 Security
+
+- [CVE-2021-23382] Bump postcss from `8.2.10` to `8.4.24` ([#4403](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4403))
+- Bump `joi` to v14 to avoid the possibility of prototype poisoning in a nested dependency ([#3952](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/3952))
+- [WS-2018-0347] Bump `sass-lint` from `1.12.1` to `1.13.0` to fix `eslint` security issue ([#4338](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4338))
+- [CVE-2022-25883] Resolve `semver` to `7.5.3` and remove unused package ([#4411](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4411), [#4686](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4686))
+- [CVE-2022-1537] Bump grunt from `1.4.1` to `1.5.3` ([#3723](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/3723))
+- [CVE-2022-0436] Bump grunt from `1.4.1` to `1.5.3` ([#3723](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/3723))
+- [CVE-2023-26136] Resolve `tough-cookie` to `4.1.3` ([#4682](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4682))
+
+### 📈 Features/Enhancements
+
+### 🐛 Bug Fixes
+
+### 🚞 Infrastructure
+
+### 📝 Documentation
+
+### 🛠 Maintenance
+
+- Adding @ZilongX and @Flyingliuhub as maintainers. ([#4137](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4137))
+- Add new MAINTAINERS to CODEOWNERS file. ([#4199](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4199))
+- Adding @BSFishy as maintainer. ([#4469](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4469))
+- [Version] Increment version to 1.3.12 ([#4656](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4656))
+
 ## [2.9.0 - 2023-07-24](https://github.com/opensearch-project/OpenSearch-Dashboards/releases/tag/2.9.0)
 
 ### 🛡 Security
@@ -151,6 +178,25 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - [Vis Augmenter Add UT for few fns ([#4516](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4516))
 - [BWC Tests] Add BWC tests for 2.7.0 and 2.8.0 ([#4023](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4023))
 
+## [1.3.11 - 2023-06-29](https://github.com/opensearch-project/OpenSearch-Dashboards/releases/tag/1.3.11)
+
+### 🛡 Security
+
+- [CVE-2022-1537] Bump grunt from `1.5.2` to `1.5.3` ([#4276](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4276))
+- [CVE-2020-15366] Bump ajv from `4.11.8` to `6.12.6` ([#3769](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/3769))
+
+### 📈 Features/Enhancements
+
+### 🐛 Bug Fixes
+
+### 🚞 Infrastructure
+
+- Upgrade the backport workflow ([#4343](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4343))
+
+### 📝 Documentation
+
+### 🛠 Maintenance
+
 ## [2.8.0 - 2023-06-06](https://github.com/opensearch-project/OpenSearch-Dashboards/releases/tag/2.8.0)
 
 ### Deprecations