Fix wilson_estimate function to use eos.mixture

[longemen3000]

julia> wilson_estimate(eos,cond.p,cond.T)
ERROR: UndefVarError: `mixture` not defined in `MultiComponentFlash`
Suggestion: check for spelling errors or missing imports.
Stacktrace:
 [1] wilson_estimate(eos::GenericCubicEOS{SoaveRedlichKwong, Float64, 2, Nothing, MultiComponentMixture{Float64, 2, String, Vector{String}, Nothing}}, p::Float64, T::Float64)
   @ MultiComponentFlash C:\Users\andre\.julia\packages\MultiComponentFlash\tqdQS\src\kvalues.jl:44
 [2] top-level scope
   @ REPL[70]:1

[codecov-commenter]

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Codecov Report

❌ Patch coverage is 0% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 58.43%. Comparing base (ad10e6e) to head (cfdbd8e).
⚠️ Report is 56 commits behind head on main.

Files with missing lines	Patch %	Lines
src/kvalues.jl	0.00%	1 Missing ⚠️
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Additional details and impacted files

@@            Coverage Diff             @@
##             main      #36      +/-   ##
==========================================
- Coverage   67.59%   58.43%   -9.16%     
==========================================
  Files          16       30      +14     
  Lines        1148     2459    +1311     
==========================================
+ Hits          776     1437     +661     
- Misses        372     1022     +650     

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