chore: rename master branch to main

Author: mpalourdio

README.md

@@ -1,7 +1,7 @@
 # intl-tel-input-ng
 
 [![CI](https://github.com/mpalourdio/ng-http-loader/actions/workflows/main.yml/badge.svg)](https://github.com/mpalourdio/ng-http-loader/actions/workflows/main.yml)
-[![Coverage Status](https://coveralls.io/repos/github/mpalourdio/intl-tel-input-ng/badge.svg?branch=master)](https://coveralls.io/github/mpalourdio/intl-tel-input-ng?branch=master)
+[![Coverage Status](https://coveralls.io/repos/github/mpalourdio/intl-tel-input-ng/badge.svg?branch=main)](https://coveralls.io/github/mpalourdio/intl-tel-input-ng?branch=main)
 [![npm](https://img.shields.io/npm/v/intl-tel-input-ng.svg)](https://www.npmjs.com/package/intl-tel-input-ng)
 [![npm](https://img.shields.io/npm/dm/intl-tel-input-ng.svg)](https://www.npmjs.com/package/intl-tel-input-ng)