CLOUDP-315307 - mck - MCO deprecation notice (#1712)

* mck - add deprecation notice and add linkages

Co-authored-by: Simon Bäumer <simon.baeumer@mongodb.com>

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Co-authored-by: Simon Bäumer <simon.baeumer@mongodb.com>

Author: nammn

README.md

@@ -1,3 +1,10 @@
+> **DEPRECATED:** This repository is deprecated but we will continue a best-effort support until November 2025. Please use the new repository at [mongodb/mongodb-kubernetes](https://github.com/mongodb/mongodb-kubernetes) instead.
+>
+> For more information on this decision - what it means and entails - see the [announcement](https://github.com/mongodb/mongodb-kubernetes/releases/tag/v1.0.0) and our [public documentation](https://www.mongodb.com/docs/kubernetes/current/).
+>
+> A detailed migration guide is available to help you transition smoothly - see [guide](https://github.com/mongodb/mongodb-kubernetes/blob/master/docs/migration/community-operator-migration.md). There will be no functional changes in the new repository - only a better and unified experience as well as improved visibility into the development process.
+
+
 # MongoDB Community Kubernetes Operator #
 
 <img align="right" src="https://mongodb-kubernetes-operator.s3.amazonaws.com/img/Leaf-Forest%402x.png">