docs: add codecov badge to README

NGPixel · web-flow · commit 2a78c6bd7eed · 2022-03-30T14:38:24.000-04:00
diff --git a/README.md b/README.md
@@ -4,6 +4,7 @@
 
 [![Release](https://img.shields.io/github/release/ietf-tools/datatracker.svg?style=flat&maxAge=300)](https://github.com/ietf-tools/datatracker/releases)
 [![License](https://img.shields.io/github/license/ietf-tools/datatracker)](https://github.com/ietf-tools/datatracker/blob/main/LICENSE)
+[![Code Coverage](https://codecov.io/gh/ietf-tools/datatracker/branch/feat/bs5/graph/badge.svg?token=V4DXB0Q28C)](https://codecov.io/gh/ietf-tools/datatracker)
 [![Nightly Dev DB Image](https://github.com/ietf-tools/datatracker/actions/workflows/dev-db-nightly.yml/badge.svg)](https://github.com/ietf-tools/datatracker/pkgs/container/datatracker-db)  
 [![Python Version](https://img.shields.io/badge/python-3.6-blue?logo=python&logoColor=white)](#prerequisites)
 [![Django Version](https://img.shields.io/badge/django-2.x-51be95?logo=django&logoColor=white)](#prerequisites)
@@ -201,4 +202,4 @@ During deployment, it is now necessary to run the management command:
 ``` shell
 ietf/manage.py collectstatic
 ````
-before activating a new release.
+before activating a new release.
