Clean up after 0.21.0 release (opensearch-project#248)

* Clean up after 0.21.0 release

Signed-off-by: xil <fridalu66@gmail.com>

* update

Signed-off-by: xil <fridalu66@gmail.com>

---------

Signed-off-by: xil <fridalu66@gmail.com>

Author: lucy66hw

release-notes/opensearch-protobufs.release-notes-0.20.0.md

@@ -5,7 +5,7 @@
 
 ### Changed
 - Revert "Revert bulk response back to without error response. ([#238](https://github.com/opensearch-project/opensearch-protobufs/pull/238))
-- Remove `lenient` and `analyzer` from `SearchRequest` and remove `analyzer` from `HighlightField` ([#241](https://github.com/opensearch-project/opensearch-protobufs/pull/241))
+
 ### Removed
 
 ### Fixed

release-notes/opensearch-protobufs.release-notes-0.21.0.md

@@ -0,0 +1,13 @@
+## Version 0.21.0 (2025-10-01) Release Notes
+
+
+### Added
+
+### Changed
+- Remove `lenient` and `analyzer` from `SearchRequest` and remove `analyzer` from `HighlightField` ([#241](https://github.com/opensearch-project/opensearch-protobufs/pull/241))
+
+### Removed
+
+### Fixed
+
+### Security

version.properties

@@ -1 +1 @@
-version=0.21.0
+version=0.22.0