Consider allowing org members to add projects to the org without enabling prebuilds

[gtsiolis]

Problem to solve

From the proposal in #16849:

We've also heard some feedback that some users don't want to enable prebuilds for a repository, which could make room for a use case where enabling prebuilds is optional, see #15281.

Proposal

There could be a use case where adding a project without prebuilds could provide some value to users like better collaboration, or using env vars in a workspace, etc.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[gtsiolis]

Closing this in favor of EXP-258.