Add support to use controller builder to build unmanaged controller

[AlmogBaku]

Problem

Currently, the controller builder doesn't support building an unmanaged controller.

To achieve this, developers are required to manually configure and wire the controller (which is the benefit of the builder).

Solution

I suggest adding a new method for the builder that specifies if it should use "unmanaged" mode:

func (blder *Builder) Unmanaged(unmanaged bool) *Builder 

The implementation for that is relatively easy and requires adding only a flag to the builder.

[AlmogBaku]

See #1822 for implementation

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