[Docs] add doc entry to explain lora fusion and use of different scales. (#4893)
* add doc entry to explain lora fusion and use of different scales.
* Apply suggestions from code review
Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>
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Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>