Correct link to OSI blog in README (opensearch-project#6498)

Also fixes spelling error in "licence".

Signed-off-by: Kartik Ganesh <gkart@amazon.com>

README.md

@@ -24,7 +24,7 @@
 
 ## 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