PyPi group endpoint: exclude projects with disabled package registry

What does this MR do and why?

Please look at the context section in the linked issue (confidential)

Screenshots or screen recordings

NA

Query Analysis

Please see the query analysis section in the linked issue (confidential)

How to set up and validate locally

Refer to the verification steps in the issue (confidential)

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #427201 (closed)