docs: Add license scan report and status (#4880)

Signed off by: fossabot <badges@fossa.com>

README.md

@@ -5,6 +5,7 @@
 [![NPM version](https://img.shields.io/npm/v/egg.svg?style=flat-square)](https://npmjs.org/package/egg)
 [![NPM quality](http://npm.packagequality.com/shield/egg.svg?style=flat-square)](http://packagequality.com/#?package=egg)
 [![NPM download](https://img.shields.io/npm/dm/egg.svg?style=flat-square)](https://npmjs.org/package/egg)
+[![FOSSA Status](https://app.fossa.com/api/projects/git%2Bgithub.com%2Feggjs%2Fegg.svg?type=shield)](https://app.fossa.com/projects/git%2Bgithub.com%2Feggjs%2Fegg?ref=badge_shield)
 
 [![Continuous Integration](https://github.com/eggjs/egg/workflows/Continuous%20integration/badge.svg)](https://github.com/eggjs/egg/actions?query=branch%3Amaster)
 [![Test coverage](https://img.shields.io/codecov/c/github/eggjs/egg.svg?style=flat-square)](https://codecov.io/gh/eggjs/egg)
@@ -58,3 +59,6 @@ To become a contributor, please follow our [contributing guide](CONTRIBUTING.md)
 ## License
 
 [MIT](LICENSE)
+
+
+[![FOSSA Status](https://app.fossa.com/api/projects/git%2Bgithub.com%2Feggjs%2Fegg.svg?type=large)](https://app.fossa.com/projects/git%2Bgithub.com%2Feggjs%2Fegg?ref=badge_large)