Remove replication of proxy project

[govindkailas]

We enable replication from our Harbor primary site to DR site. Something that we notice is whenever it reaches the proxy projects the replications are failing with the below error,
http status code: 403, body: {"errors":[{"code":"DENIED","message":"denied: can not push artifact to a proxy project: dockerhub-proxy-cache"}]}

If this is by design, please consider skipping proxy project from replication.

[stonezdj]

It is possible to exclude the proxy cache project when pulling images to a remote, we could check the current project is proxy cache project.

[stonezdj]

Create proxy cache project dockhub_proxy in server A and B. and setup an event-based replication, it seems that this error can not reproduce now.
When caching an image in A/dockerhub_proxy/library/hello-world:latest , it trigger a replication job which replicate the image to A/dockerhub_proxy/library/hello-world:latest to B/dockerhub_proxy/library/hello-world:latest.
Before replication, server A check if the artifact exists in the remote registry, it sends a HEAD request the server B. check if the B/dockerhub_proxy/library/hello-world:latest exist, because B/dockerhub_proxy is a proxy-cache project, it proxy the request to dockerhub and HTTP 200 to the server A eventually, then server A consider this image already exists in server B. and mark this replication job succeed.

It is better to solve this issue in replication, but it seems not urgent.

[pjastrzabek]

Before 2.5.x versions we had a working helm charts replication into proxy project.

That harbor project had 2 functions:

• it was a proxy project for docker images
• and was holding replicated helm charts

After update to 2.5.x helm chart replication (explicitly selected in replication rule) does not work (All created replication tasks are skipped with a log "skip create replication task because of dest limitation")