issue#1931: Cleanup XML of transform Set Variable

[sramazzina]

Cleanup XML of transform Set Variable.
Some improvements on language string.
Added integration tests.

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[hansva]

@usbrandon , what is the reason for marking it as a draft?

[sramazzina]

Brandon noticed that there are some imports that could be optimized. I didn't noticed that and I agree with him. I will take care about that today. I asked him to mark the PR as draft because I was on holiday and he kindly did it.

[hansva]

Alright, I was just wondering as there was no discussion or reason here as to why it was changed to draft.