docs(readme): remove Greenkeeper badge

Author: greenkeeper[bot]

README.md

@@ -2,7 +2,6 @@
 
 [![GitHub Package Registry version](https://img.shields.io/github/release/bifravst/eslint-config-typescript.svg?label=GPR&logo=github)](https://github.com/bifravst/eslint-config-typescript/packages/26698)
 [![GitHub Actions](https://github.com/bifravst/eslint-config-typescript/workflows/Semantic%20Release/badge.svg)](https://github.com/bifravst/eslint-config-typescript/actions)
-[![Greenkeeper badge](https://badges.greenkeeper.io/bifravst/eslint-config-typescript.svg)](https://greenkeeper.io/)
 [![semantic-release](https://img.shields.io/badge/%20%20%F0%9F%93%A6%F0%9F%9A%80-semantic--release-e10079.svg)](https://github.com/semantic-release/semantic-release)
 [![Commitizen friendly](https://img.shields.io/badge/commitizen-friendly-brightgreen.svg)](http://commitizen.github.io/cz-cli/)
 [![code style: prettier](https://img.shields.io/badge/code_style-prettier-ff69b4.svg)](https://github.com/prettier/prettier/)