Update README.md

Co-authored-by: Kathrin Koebel <kathrin@koebel.ch>

Author: S-Panta

README.md

@@ -33,7 +33,7 @@ It allows users to:
 
 ### App Installation With [oCIS Deployment](https://github.com/owncloud/ocis/tree/master/deployments/examples/ocis_full)
 
-1. Copy [`deployments/mdpresentation-viewer.yaml`](./deployments/mdpresentation-viewer.yaml) into the [web_extensions](https://github.com/owncloud/ocis/tree/master/deployments/examples/ocis_full/web_extension)
+1. Copy [`deployments/mdpresentation-viewer.yml`](./deployments/mdpresentation-viewer.yml) into the [web_extensions](https://github.com/owncloud/ocis/tree/master/deployments/examples/ocis_full/web_extension)
 subfolder of oCIS full deployment example.
 2. Add `MDVIEWER=:web_extensions/mdpresentation-viewer.yml` to the `## oCIS Web Extensions ##` section of the `.env` file of your installation (file is located in `deployments/examples/ocis_full`).\ Add that variable in the `COMPOSE_FILE` variable at the last line.
 3. Run `docker compose up` to run oCIS with the extensions