Add employer for Diego (#1885)

Fixes #1884

Author: ocelotl

README.md

@@ -131,7 +131,7 @@ Meeting notes are available as a public [Google doc](https://docs.google.com/doc
 Approvers ([@open-telemetry/python-approvers](https://github.com/orgs/open-telemetry/teams/python-approvers)):
 
 - [Aaron Abbott](https://github.com/aabmass), Google
-- [Diego Hurtado](https://github.com/ocelotl)
+- [Diego Hurtado](https://github.com/ocelotl), Lightstep
 - [Owais Lone](https://github.com/owais), Splunk
 - [Srikanth Chekuri](https://github.com/lonewolf3739)