Correct link to OSI blog in README (#6498) (#6502)

Also fixes spelling error in "licence".


(cherry picked from commit 4c37c8f)

Signed-off-by: Kartik Ganesh <gkart@amazon.com>
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

Author: opensearch-trigger-bot[bot]

README.md

@@ -9,7 +9,7 @@
 
 ## Welcome!
 
-**OpenSearch** is [a community-driven, open source fork](https://aws.amazon.com/blogs/opensource/introducing-opensearch/) of [Elasticsearch](https://en.wikipedia.org/wiki/Elasticsearch) and [Kibana](https://en.wikipedia.org/wiki/Kibana) following the [licence change](https://opensource.org/node/1099) in early 2021. We're looking to sustain (and evolve!) a search and analytics suite for the multitude of businesses who are dependent on the rights granted by the original, [Apache v2.0 License](LICENSE.txt).
+**OpenSearch** is [a community-driven, open source fork](https://aws.amazon.com/blogs/opensource/introducing-opensearch/) of [Elasticsearch](https://en.wikipedia.org/wiki/Elasticsearch) and [Kibana](https://en.wikipedia.org/wiki/Kibana) following the [license change](https://blog.opensource.org/the-sspl-is-not-an-open-source-license/) in early 2021. We're looking to sustain (and evolve!) a search and analytics suite for the multitude of businesses who are dependent on the rights granted by the original, [Apache v2.0 License](LICENSE.txt).
 
 ## Project Resources