[DOC] Add Flower to MXNet ecosystem (#20038)

* add flower decsription and logo to mxnet ecosystem

* add name to contributors

Author: mariaboerner1987

CONTRIBUTORS.md

@@ -291,6 +291,7 @@ List of Contributors
 * [Andrzej Kotlowski](https://github.com/anko-intel)
 * [Yingxiao Du](https://github.com/Duconnor)
 * [Bartosz Kuncer](https://github.com/bartekkuncer)
+* [Maria Boerner](https://github.com/mariaboerner1987)
 
 Label Bot
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docs/static_site/src/assets/img/flower_icon.png

@@ -25,6 +25,10 @@
   link: https://autogluon.mxnet.io
 
 ecosystem_other:
+- title: Flower
+  text: Flower is an agnostic federated learning framework. Federate any workload, any machine learning framework, and any programming language.
+  icon: /assets/img/flower_icon.png
+  link: https://flower.dev/
 - title: InsightFace
   text: State-of-the-art face detection and face recognition repository, including ArcFace loss and RetinaFace implementation
   link: https://github.com/deepinsight/insightface