Fix doctest (StaticArrays output changed)

[schillic]

┌ Error: doctest failure in ~/work/LazySets.jl/LazySets.jl/src/Approximations/overapproximate.jl:909-918
│ 
│ ```jldoctest oa_tm1
│ julia> X = box_approximation(Z)
│ Hyperrectangle{Float64, Vector{Float64}, Vector{Float64}}([1.0, -2.1], [2.5, 6.5])
│ 
│ julia> Y = evaluate(vTM[1], vTM[1].dom) × evaluate(vTM[2], vTM[2].dom)
│ [-1.5, 3.5] × [-8.60001, 4.40001]
│ 
│ julia> H = convert(Hyperrectangle, Y) # this IntevalBox is the same as X
│ Hyperrectangle{Float64, StaticArrays.SVector{2, Float64}, StaticArrays.SVector{2, Float64}}([1.0, -2.1000000000000005], [2.5, 6.500000000000001])
│ ```
│ 
│ Subexpression:
│ 
│ H = convert(Hyperrectangle, Y) # this IntevalBox is the same as X
│ 
│ Evaluated output:
│ 
│ Hyperrectangle{Float64, StaticArraysCore.SVector{2, Float64}, StaticArraysCore.SVector{2, Float64}}([1.0, -2.1000000000000005], [2.5, 6.500000000000001])
│ 
│ Expected output:
│ 
│ Hyperrectangle{Float64, StaticArrays.SVector{2, Float64}, StaticArrays.SVector{2, Float64}}([1.0, -2.1000000000000005], [2.5, 6.500000000000001])
│ 
│   diff = Hyperrectangle{Float64, StaticArrays.SVector{2, StaticArraysCore.SVector{2, Float64}, StaticArrays.SVector{2, StaticArraysCore.SVector{2, Float64}}([1.0, -2.1000000000000005], [2.5, 6.500000000000001])