feat(docs): Create JobSet adopters page (#852)

Author: andreyvelich

site/content/en/docs/adopters/_index.md

@@ -0,0 +1,22 @@
+---
+title: "Adopters"
+linkTitle: "Adopters"
+weight: 20
+menu:
+  main:
+    weight: 30
+description: >
+  Where and how JobSet is used
+aliases:
+  - /adopters
+---
+
+Below is a list of organizations and projects that use JobSet in production along with the integrations they use.
+If you are using JobSet, feel free to open a pull request to update this list.
+
+## Adopters
+
+| Organization                                                                                          | Description                                    | Contact                                          |
+| ----------------------------------------------------------------------------------------------------- | ---------------------------------------------- | ------------------------------------------------ |
+| [Google TPU Training](https://cloud.google.com/kubernetes-engine/docs/tutorials/tpu-multislice-kueue) | Large scale distributed AI/ML training on TPUs | [@ahg-g](https://github.com/ahg-g)               |
+| [Kubeflow Trainer](https://github.com/kubeflow/trainer)                                               | Job management for distributed AI/ML training  | [@andreyvelich](https://github.com/andreyvelich) |