Remove remaining SLA references

Signed-off-by: cgunasree08 <Chintha.Gunasree@progress.com>

Author: cgunasree08

README.md

@@ -3,8 +3,6 @@
 [![Build Status](https://badge.buildkite.com/5b595abc5c79a69fa4da5aeb14efd8e9104ec3a4ca53fc904a.svg?branch=master)](https://buildkite.com/chef-oss/chef-mixlib-cli-master-verify)
 [![Gem Version](https://badge.fury.io/rb/mixlib-cli.svg)](https://badge.fury.io/rb/mixlib-cli)
 
-**Umbrella Project**: [Chef Foundation](https://github.com/chef/chef-oss-practices/blob/master/projects/chef-foundation.md)
-
 Mixlib::CLI provides a class-based command line option parsing object, like the one used in Chef, Ohai and Relish. To use in your project:
 
 ```ruby