feat(core): enable map function on transform option

[luizfbicalho]

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)
This is an Idea to create a function to map the result on the FormlySelectOptionsPipe

What is the current behavior? (You can also link to an open issue here)

This is the implementation of the #3624

What is the new behavior (if this is a feature change)?

Please check if the PR fulfills these requirements

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[luizfbicalho]

@aitboudad I coudn't figure out the problem, I added the same map to my project with others components