Drafted 2.11 release notes. (opensearch-project#1004)

* Drafted 2.11 release notes.

Signed-off-by: AWSHurneyt <hurneyt@amazon.com>

* Drafted 2.11 release notes.

Signed-off-by: AWSHurneyt <hurneyt@amazon.com>

---------

Signed-off-by: AWSHurneyt <hurneyt@amazon.com>
Signed-off-by: Joshua Au <joshuahyau@gmail.com>

release-notes/opensearch-index-management.release-notes-2.11.0.0.md

@@ -0,0 +1,21 @@
+## Version 2.11.0.0 2023-10-11
+
+Compatible with OpenSearch 2.10.0
+
+### Maintenance
+* Increment version to 2.11.0-SNAPSHOT. ([#922](https://github.com/opensearch-project/index-management/pull/922))
+
+### Enhancements
+* Provide unique id for each rollup job and add debug logs. ([#968](https://github.com/opensearch-project/index-management/pull/968))
+
+### Bug fixes
+* Fix auto managed index always have -2 seqNo bug. ([#924](https://github.com/opensearch-project/index-management/pull/924))
+
+### Infrastructure
+* Upload docker test cluster log. ([#964](https://github.com/opensearch-project/index-management/pull/964))
+* Reduce test running time. ([#965](https://github.com/opensearch-project/index-management/pull/965))
+* Parallel test run. ([#966](https://github.com/opensearch-project/index-management/pull/966))
+* Security test filtered. ([#969](https://github.com/opensearch-project/index-management/pull/969))
+
+### Documentation
+* Added 2.11 release notes. ([#1004](https://github.com/opensearch-project/index-management/pull/1004))