message: Add Monzo to ADOPTERS.md
diff: | [Taxfix](https://taxfix.de/) | [Sami Ur Rehman](https://github.com/samiurrehman92) | Developer's portal with software catalog at it's core. Hosts API Specs, Tech Docs, Tech Radar and some custom plugins. |
  | [Busuu](https://busuu.com/) | [Adam Tester](https://github.com/adamtester) | Developer portal with service catalog, API docs, Event docs, service templating, and cost insights. |
  | [Loadsmart](https://loadsmart.com/) | [Loadsmart](https://github.com/loadsmart) | Improve services visibility and operations for service owners and developers. |
  +| [Monzo](https://monzo.com/) | [@WillSewell](https://github.com/WillSewell), [@joechrisellis](https://github.com/joechrisellis) | Developer portal showing metadata and docs for over 2000 microservices. We have built a number of plugins such as a UI for our system to measure [software excellence](https://monzo.com/blog/2021/09/15/how-we-measure-software-excellence), and a UI to show deployment and config change events. |
  