scalarize does not fully scalarize

[YingboMa]

julia> using Symbolics

julia> @variables  pos[1:3]
1-element Vector{Symbolics.Arr{Num, 1}}:
 pos[1:3]

julia> Symbolics.scalarize(pos/norm(pos))
3-element Vector{Num}:
 pos[1] / sqrt(Symbolics._mapreduce(#396, +, pos, Colon(), (:init => false,)))
 pos[2] / sqrt(Symbolics._mapreduce(#396, +, pos, Colon(), (:init => false,)))
 pos[3] / sqrt(Symbolics._mapreduce(#396, +, pos, Colon(), (:init => false,)))

Ref: SciML/ModelingToolkit.jl#2920

[ufechner7]

Would be nice if this could be fixed.