Value Statement

Ensure the issue title clearly reflects the value of this user story to the
intended persona. (Explain the "WHY")

The klusterlet has supported forward proxy. The cluster proxy addon needs to support 

forward proxy too.

Definition of Done for Engineering Story Owner (Checklist)

• The cluster proxy addon can work when the managed cluster is behind a HTTP/HTTPS forward proxy server .

Development Complete

• The code is complete.
• Functionality is working.
• Any required downstream Docker file changes are made.

Tests Automated

• [x] Unit/function tests have been automated and incorporated into the
  build.
• [x] 100% automated unit/function test coverage for new or changed APIs.

Secure Design

• [ ] Security has been assessed and incorporated into your threat model.

Multidisciplinary Teams Readiness

• [x] Create an informative documentation issue using the [Customer
  Portal_doc_issue template](
  https://github.com/stolostron/backlog/issues/new?assignees=&labels=squad%3Adoc&template=doc_issue.md&title=),
  and ensure doc acceptance criteria is met. Link the development issue to
  the doc issue.

     *https://issues.redhat.com/browse/ACM-9274*

• [x] Provide input to the QE team, and ensure QE acceptance criteria
  (established between story owner and QE focal) are met.

Support Readiness

• [ ] The must-gather script has been updated.