Add CLA ref to CONTRIBUTING.md

Description

Add reference to signing a CLA to the CONTRIBUTING.md file

Environment

None
Fixed

Assignee

Steve Ebersole

Reporter

Steve Ebersole

Fix versions

Labels

None

backPortable

None

Suitable for new contributors

None

Requires Release Note

None

Pull Request

None

backportDecision

None

Components

Affects versions

Priority

Major
Configure