Add release notes for 2.15 (#2536) (#3028)

* add release notes for 2.15

Signed-off-by: Bhavana Ramaram <rbhavna@amazon.com>
(cherry picked from commit 1a16659)

Co-authored-by: Bhavana Ramaram <rbhavna@amazon.com>

release-notes/opensearch-ml-common.release-notes-2.15.0.0.md

@@ -0,0 +1,42 @@
+## Version 2.15.0.0 Release Notes
+
+Compatible with OpenSearch 2.15.0.0
+
+### Features
+* Add connector tool ([#2516](https://github.com/opensearch-project/ml-commons/pull/2516))
+* guardrails model support ([#2491](https://github.com/opensearch-project/ml-commons/pull/2491))
+
+
+### Enhancements
+* hanlde the throttling error in the response header ([#2442](https://github.com/opensearch-project/ml-commons/pull/2442))
+* Implementing retry for remote connector to mitigate throttling issue ([#2462](https://github.com/opensearch-project/ml-commons/pull/2462))
+* ml inference ingest processor support for local models ([#2508](https://github.com/opensearch-project/ml-commons/pull/2508))
+* add setting to allow private IP ([#2534](https://github.com/opensearch-project/ml-commons/pull/2534))
+
+
+### Bug Fixes
+* fix memory CB bugs and upgrade UTs to compatible with core changes ([#2469](https://github.com/opensearch-project/ml-commons/pull/2469))
+* fix error of ML inference processor in foreach processor ([#2474](https://github.com/opensearch-project/ml-commons/pull/2474))
+* fix error message with unwrapping the root cause ([#2458](https://github.com/opensearch-project/ml-commons/pull/2458))
+* adding immediate refresh to delete model group request ([#2514](https://github.com/opensearch-project/ml-commons/pull/2514))
+* Fix model still deployed after calling undeploy API ([#2510](https://github.com/opensearch-project/ml-commons/pull/2510))
+* Fix bedrock embedding generation issue ([#2495](https://github.com/opensearch-project/ml-commons/pull/2495))
+
+
+### Documentation
+* add a connector blueprint for Amazon Comprehend APIs ([#2470](https://github.com/opensearch-project/ml-commons/pull/2470))
+* add titan embeeding v2 to blueprint ([#2480](https://github.com/opensearch-project/ml-commons/pull/2480))
+* tutorial: generate embedding for arrays of object  ([#2477](https://github.com/opensearch-project/ml-commons/pull/2477))
+* Small fix in blueprint docs ([#2501](https://github.com/opensearch-project/ml-commons/pull/2501))
+* Titan Embedding Connector Blueprint content referenced by users of OpenSearch 2.11 version ([#2519](https://github.com/opensearch-project/ml-commons/pull/2519))
+
+
+### Infrastructure
+* add IT for flow agent with CatIndexTool ([#2425](https://github.com/opensearch-project/ml-commons/pull/2425))
+* Remove strict version dependency to compile minimum compatible version ([#2486](https://github.com/opensearch-project/ml-commons/pull/2486))
+* add IT flow agent with search index tool ([#2460](https://github.com/opensearch-project/ml-commons/pull/2460))
+* fix flaky IT ([#2530](https://github.com/opensearch-project/ml-commons/pull/2530))
+
+### Maintenance
+* Updating security reachout email ([#2445](https://github.com/opensearch-project/ml-commons/pull/2445))
+