[readme] change SLA to RTM per OSS Practices
the Chef OSS Practices documentation refers to response time with the
term Response Time Maximum (RTM) instead of Service Level Agreement.
this change reflects that language.
link:
@@ -19,9 +19,9 @@ For more information see:
**Project State**: [Active](https://github.com/chef/chef-oss-practices/blob/master/repo-management/repo-states.md#active)
-**Issues Response SLA**: 5 business days
+**Issues Response Time Maximum**: 5 business days
-**Pull Request Response SLA**: 5 business days
+**Pull Request Response Time Maximum**: 5 business days
## Components
