chore: remove github workflows [skip ci]

Author: mdonnalley

.github/workflows/ci.yml

@@ -5,8 +5,6 @@ eslint config for oclif
 
 [![Version](https://img.shields.io/npm/v/eslint-config-oclif.svg)](https://npmjs.org/package/eslint-config-oclif)
 [![CircleCI](https://circleci.com/gh/oclif/eslint-config-oclif/tree/main.svg?style=svg)](https://circleci.com/gh/oclif/eslint-config-oclif/tree/main)
-[![Appveyor CI](https://ci.appveyor.com/api/projects/status/github/oclif/eslint-config-oclif?branch=main&svg=true)](https://ci.appveyor.com/project/heroku/eslint-config-oclif/branch/main)
-[![Greenkeeper](https://badges.greenkeeper.io/oclif/eslint-config-oclif.svg)](https://greenkeeper.io/)
 [![Known Vulnerabilities](https://snyk.io/test/npm/eslint-config-oclif/badge.svg)](https://snyk.io/test/npm/eslint-config-oclif)
 [![Downloads/week](https://img.shields.io/npm/dw/eslint-config-oclif.svg)](https://npmjs.org/package/eslint-config-oclif)
 [![License](https://img.shields.io/npm/l/eslint-config-oclif.svg)](https://github.com/oclif/eslint-config-oclif/blob/main/package.json)