[Dev] Check warning when using ExaModels (constraint)

[jbcaillau]

when installing, most likely conflict with CTModels.constraint

  108 dependencies successfully precompiled in 94 seconds. 11 already precompiled.
     Testing Running tests...
WARNING: using ExaModels.constraint in module Main conflicts with an existing identifier.
[█░░░░░░░░░░░] ✓ [01/12] test_aqua.jl (13.3s)