Remove compiler lowerings from the user documentation

[JinShil]

To see the effect of this you need to use a recent compiler that includes dlang/dmd#9068 DAutoTest currently uses 2.079 so you will not see the effect in its output.

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Testing this PR locally

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[JinShil]

This doesn't work the way I thought it did. It appears I'll have to make a change to dlang/dmd#9068