fix(ci): since tests are run before every release and circleci change…

…d it's way of doing docker in docker...

README.md

@@ -1,6 +1,6 @@
 # MailChecker
 
-[![Build Status](https://img.shields.io/circleci/project/github/FGRibreau/mailchecker.svg)](https://circleci.com/gh/FGRibreau/mailchecker/) [![Deps](	https://img.shields.io/david/FGRibreau/mailchecker.svg)](https://david-dm.org/FGRibreau/mailchecker) [![NPM version](https://img.shields.io/npm/v/mailchecker.svg)](http://badge.fury.io/js/mailchecker) [![Gem version](https://img.shields.io/gem/v/ruby-mailchecker.svg)](http://badge.fury.io/js/mailchecker) [![PyPi version](https://img.shields.io/pypi/v/mailchecker.svg)](https://pypi.org/project/mailchecker/#history) [![Packagist version](https://img.shields.io/packagist/v/FGRibreau/mailchecker.svg)](https://packagist.org/packages/fgribreau/mailchecker) [![Cargo version](https://img.shields.io/crates/v/mailchecker.svg)](https://crates.io/crates/mailchecker) [![Downloads](http://img.shields.io/npm/dm/mailchecker.svg)](https://www.npmjs.com/package/mailchecker)
+[![Deps](	https://img.shields.io/david/FGRibreau/mailchecker.svg)](https://david-dm.org/FGRibreau/mailchecker) [![NPM version](https://img.shields.io/npm/v/mailchecker.svg)](http://badge.fury.io/js/mailchecker) [![Gem version](https://img.shields.io/gem/v/ruby-mailchecker.svg)](http://badge.fury.io/js/mailchecker) [![PyPi version](https://img.shields.io/pypi/v/mailchecker.svg)](https://pypi.org/project/mailchecker/#history) [![Packagist version](https://img.shields.io/packagist/v/FGRibreau/mailchecker.svg)](https://packagist.org/packages/fgribreau/mailchecker) [![Cargo version](https://img.shields.io/crates/v/mailchecker.svg)](https://crates.io/crates/mailchecker) [![Downloads](http://img.shields.io/npm/dm/mailchecker.svg)](https://www.npmjs.com/package/mailchecker)
 
 [![Get help on Codementor](https://cdn.codementor.io/badges/get_help_github.svg)](https://www.codementor.io/francois-guillaume-ribreau?utm_source=github&utm_medium=button&utm_term=francois-guillaume-ribreau&utm_campaign=github)  [![available-for-advisory](https://img.shields.io/badge/available%20for%20advising-yes-ff69b4.svg?)](http://bit.ly/2c7uFJq) ![extra](https://img.shields.io/badge/actively%20maintained-yes-ff69b4.svg?)