Use Codecov for coverage reporting

Author: ramsey

.github/workflows/continuous-integration.yml

@@ -79,10 +79,5 @@ jobs:
           composer-options: "${{ matrix.composer-options }}"
       - name: "Run unit tests"
         run: "./vendor/bin/phpunit --colors=always --coverage-clover build/logs/clover.xml"
-      - name: "Publish coverage report to Coveralls"
-        continue-on-error: true
-        env:
-          COVERALLS_REPO_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        run: |
-          composer global --ansi require php-coveralls/php-coveralls
-          php-coveralls --ansi -vv --coverage_clover=build/logs/clover.xml
+      - name: "Publish coverage report to Codecov"
+        uses: "codecov/codecov-action@v1"

README.md

@@ -3,11 +3,11 @@
 This package makes it simple to integrate your application with [OAuth 2.0](http://oauth.net/2/) service providers.
 
 [![Gitter Chat](https://img.shields.io/badge/gitter-join_chat-brightgreen.svg?style=flat-square)](https://gitter.im/thephpleague/oauth2-client)
-[![Source Code](http://img.shields.io/badge/source-thephpleague/oauth2--client-blue.svg?style=flat-square)](https://github.com/thephpleague/oauth2-client)
+[![Source Code](https://img.shields.io/badge/source-thephpleague/oauth2--client-blue.svg?style=flat-square)](https://github.com/thephpleague/oauth2-client)
 [![Latest Version](https://img.shields.io/github/release/thephpleague/oauth2-client.svg?style=flat-square)](https://github.com/thephpleague/oauth2-client/releases)
 [![Software License](https://img.shields.io/badge/license-MIT-brightgreen.svg?style=flat-square)](https://github.com/thephpleague/oauth2-client/blob/master/LICENSE)
 [![Build Status](https://img.shields.io/github/workflow/status/thephpleague/oauth2-client/CI?label=CI&logo=github&style=flat-square)](https://github.com/thephpleague/oauth2-client/actions?query=workflow%3ACI)
-[![Coverage Status](https://img.shields.io/coveralls/thephpleague/oauth2-client/master.svg?style=flat-square)](https://coveralls.io/r/thephpleague/oauth2-client?branch=master)
+[![Codecov Code Coverage](https://img.shields.io/codecov/c/gh/thephpleague/oauth2-client?label=codecov&logo=codecov&style=flat-square)](https://codecov.io/gh/thephpleague/oauth2-client)
 [![Total Downloads](https://img.shields.io/packagist/dt/league/oauth2-client.svg?style=flat-square)](https://packagist.org/packages/league/oauth2-client)
 
 ---

docs/index.md

@@ -12,7 +12,7 @@ League/oauth2-client
 [![Latest Version](https://img.shields.io/github/release/thephpleague/oauth2-client.svg?style=flat-square)](https://github.com/thephpleague/oauth2-client/releases)
 [![Software License](https://img.shields.io/badge/license-MIT-brightgreen.svg?style=flat-square)](https://github.com/thephpleague/oauth2-client/blob/master/LICENSE)
 [![Build Status](https://img.shields.io/github/workflow/status/thephpleague/oauth2-client/CI?label=CI&logo=github&style=flat-square)](https://github.com/thephpleague/oauth2-client/actions?query=workflow%3ACI)
-[![Coverage Status](https://img.shields.io/coveralls/thephpleague/oauth2-client/master.svg?style=flat-square)](https://coveralls.io/r/thephpleague/oauth2-client?branch=master)
+[![Codecov Code Coverage](https://img.shields.io/codecov/c/gh/thephpleague/oauth2-client?label=codecov&logo=codecov&style=flat-square)](https://codecov.io/gh/thephpleague/oauth2-client)
 [![Total Downloads](https://img.shields.io/packagist/dt/league/oauth2-client.svg?style=flat-square)](https://packagist.org/packages/league/oauth2-client)
 
 The OAuth2 login flow, seen commonly around the web in the form of "Connect with Facebook/Google/etc." buttons, is a very