improve service manager label list related scenarios

[alexwo]

SM list labels optimizations

Motivation

Improve sm performance by reducing the amount of data that is fetched from the labels table and sent to the service manager app.

Approach

• Use repository.Count instead of repository.List(ctx, types.VisibilityType,etc..) when ever possible
• Use repository.ListNoLabels instead of repository.List when ever possible

Pull Request status

• [x] Refactoring