Error rooting simple univariate polynomials

[blegat]

With BigFloat, we get twice the same one and discard the 3 one.

julia> f2 = 4x^4 - 32x^3 + 88x^2 - 96x + 36

julia> collect(@set f2 == 0.0)
2-element Vector{Vector{Float64}}:
 [1.0000000000000029]
 [2.9999999999999996]

julia> collect(@set f2 == 0)
2-element Vector{Vector{BigFloat}}:
 [0.9999999382555684845569735071540710234626731208952353455422252878631453679170171]
 [1.000000061744437206395646738036651859287108299143315536935410652898126304677362]