chore(readme): remove Greenkeeper badge (#289)

Co-authored-by: greenkeeper[bot] <23040076+greenkeeper[bot]@users.noreply.github.com>
Co-authored-by: Vittorio Guerriero <[email protected]>

Author: greenkeeper[bot]

README.md

@@ -2,7 +2,7 @@
 ![Test](https://github.com/Typescript-TDD/ts-auto-mock/workflows/Test/badge.svg)
 [![npm version](https://badge.fury.io/js/ts-auto-mock.svg)](https://badge.fury.io/js/ts-auto-mock)
 [![Downloads](https://img.shields.io/npm/dw/ts-auto-mock.svg)](https://www.npmjs.com/package/ts-auto-mock) 
-[![Greenkeeper badge](https://badges.greenkeeper.io/Typescript-TDD/ts-auto-mock.svg)](https://greenkeeper.io/)
+
 
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