Allow a custom recommender to be set via annotation or label on the namespace

[brocoppler]

Checklist

• [x] I have signed the CLA
• [x] I have updated/added any relevant documentation

Description

What's the goal of this PR? To allow recommenders to be set on VPAs without being overwritten and provide a label that can be used to have goldilocks manage the setting of a given custom recommender

What changes did you make? The spec is no longer always overwritten by the goldilocks controller, but rather it is additive when not explicitly a goldilocks managed field

What alternative solution should we consider, if any? The label can be the ONLY way to set a custom recommender if using goldilocks No label can be provided by goldilocks, but allow recommenders to be added and not overwritten still